PCA 100-2007, Prescriptive Design of Exterior Concrete Walls
for One- and Two-Family Dwellings
i
Prescriptive Design ofExterior Concrete Wallsfor One- and Two-Family Dwellings
An organization of cement companies toimprove and extend the uses of portlandcement and concrete through marketdevelopment, engineering, research,education, and public affairs work.
PCA 100-2007
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ii
© 2007 Portland Cement AssociationAll rights reserved. No part of this publication may be reproduced, stored in a retrieval system, ortransmitted in any form or by any means, electronic, mechanical, photocopying, recording, or other-wise, without the prior permission of the copyright owner.Portland Cement Association (“PCA”) is a not-for-profit organization and provides this publi-cation solely for the continuing education of qualified professionals. THIS PUB LICA TIONSHOULD ONLY BE USED BY QUALIFIED PROFESSIONALS who possess all required license(s),who are competent to evaluate the significance and limitations of the information providedherein, and who accept total re sponsibility for the application of this information. OTHERREADERS SHOULD OBTAIN ASSISTANCE FROM A QUALIFIED PROFESSIONAL BEFORE PRO -CEEDING.
EB560
WARNING: Contact with wet (unhardened) concrete, mortar, cement, or cement mixtures can causeSKIN IRRITATION, SEVERE CHEMICAL BURNS (THIRD DEGREE), or SERIOUS EYE DAMAGE. Frequentexposure may be associated with irritant and/or allergic contact dermatitis. Wear waterproof gloves,a long-sleeved shirt, full-length trousers, and proper eye protection when working with these mate-rials. If you have to stand in wet concrete, use waterproof boots that are high enough to keepconcrete from flowing into them. Wash wet concrete, mortar, cement, or cement mixtures fromyour skin immediately. Flush eyes with clean water immediately after contact. Indirect contact throughclothing can be as serious as direct contact, so promptly rinse out wet concrete, mortar, cement,or cement mixtures from clothing. Seek immediate medical attention if you have persistent or severediscomfort.
PCA AND ITS MEMBERS MAKE NO EXPRESS OR IMPLIED WARRANTY WITH RESPECT TO THISPUBLICATION OR ANY INFORMATION CONTAINED HEREIN. IN PARTICULAR, NO WARRANTYIS MADE OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. PCA AND ITSMEMBERS DISCLAIM ANY PRODUCT LIABILITY (IN CLUDING WITHOUT LIMITATION ANYSTRICT LIABILITY IN TORT) IN CONNECTION WITH THIS PUBLICATION OR ANY INFORMATIONCONTAINED HEREIN.
Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
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PREFACEThis is the first edition of the Portland Cement Association’s (PCA) PrescriptiveDesign of Exterior Concrete Walls for One- and Two-Family Dwellings. This con -sensus standard was developed by the PCA’s National Standards DevelopmentCommittee (Committee) that operates under PCA’s American National StandardsInstitute (ANSI) approved “Procedures for the Development and Maintenance ofPortland Cement Association Standards.” The consensus process of PCA forpromulgating standards is accredited by ANSI. The Committee is balanced andwas formed and operated in accordance with the PCA procedures.
The Committee acknowledges and is grateful for the contributions of the numer -ous engineers, researchers, producers and others who have contributed to thebody of knowledge on the subject. The Committee wishes to also express theirappreciation for the contributions of the Residential Subcommittee, withoutwhose work this Standard could not have been completed. The Committee alsoacknowledges the Portland Cement Association, American Iron and Steel Insti -tute and Steel Framing Alliance for their contributions which permitted thedetails in Chapter 6 for connecting cold-formed steel framing to concrete wallsto be developed.
While every effort has been made to produce a publication free of errors, thereare likely to be some that will not be discovered until after publication. If errorsare found, errata will be published and posted on the Portland CementAssociation’s website at:
<www.cement.org/bookstore/EB560_errata.pdf>.
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Portland Cement AssociationNational Standards Development Committee
Buck BarkerRVT Engineering Services
David R. Jarmul, P.E.American Polysteel, LLC
Kelly E. Cobeen, P.E., S.E.Cobeen & Associates Structural Engineering
Kenneth G. Kazanis, ChairLafarge North America
Barry DescheneauxHolcim (US), Inc.
Thomas L. Klemens, P.E.Hanley Wood Business Media
Kelvin L. Doerr, P.E.Reward Wall Systems, Inc.
Lionel Lemay, P.E., S.E.National Ready Mixed Concrete Association
Nader R. Elhajj, P.E.FrameCAD Solutions
Paul M. LynchCounty of Fairfax, VA
Daniel W. Falconer, P.E.American Concrete Institute
Robert E. Sculthorpe, P.Eng.Tegrant Corporation
David A. HenneyPhoenix Systems & Components
Stephen S. Szoke, P.E., Sec. Non-votingPortland Cement Association
Edward J. TrinkleHomebuilder
Residential Subcommittee
Kelly E. Cobeen, P.E., S.E.Cobeen & Associates Structural Engineering
Lionel Lemay, P.E., S.E.National Ready Mixed Concrete Association
Barry DescheneauxHolcim (US), Inc.
Joe LymanInsulating Concrete Form Association
Kelvin L. Doerr, P.E.Reward Wall Systems, Inc.
Paul M. LynchCounty of Fairfax, VA
Nader R. Elhajj, P.E.FrameCAD Solutions
Joseph J. Messersmith, Jr., P.E., Chair Portland Cement Association
Satyendra K. Ghosh, Ph.D.S.K. Ghosh Associates Inc.
Edward Sauter, NCARBTilt-Up Concrete Association
David A. HenneyPhoenix Systems & Components
Robert E. Sculthorpe, P.Eng.Tegrant Corporation
David R. Jarmul, P.E.American Polysteel, LLC
Stephen V. Skalko, P.E., Sec. Non-votingPortland Cement Association
Thomas L. Klemens, P.E.Hanley Wood Business Media
Edward J. TrinkleHomebuilder
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Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iii
National Standards Development Committee. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iv
Residential Subcommittee . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iv
LIST OF TABLES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xi
LIST OF FIGURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xv
CHAPTER 1. GENERAL. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
1.1 Scope. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
1.2 Limitations on Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
1.2.1 Flood Prone Areas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
1.2.2 Seismic Design Categories C, D0, D1 and D2. . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
1.2.3 Seismic Design Category E . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
1.2.4 Conflicting Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
1.3 Requirements for Seismic Design Category C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
1.4 Forming System Limitations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
1.5 Construction Documents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
1.6 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
1.7 Reference Standards. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5
CHAPTER 2. GENERAL REQUIREMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
2.1 Dimensions of Walls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
2.1.1 Flat Wall Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
2.1.2 Waffle-Grid Wall Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
2.1.3 Screen-Grid Wall System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
2.2 Concrete . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
2.2.1 Concrete and Materials for Concrete . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
2.2.2 Concrete Mixing and Delivery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
2.2.3 Maximum Aggregate Size. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
2.2.4 Proportioning and Slump of Concrete. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
2.2.5 Compressive Strength. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
2.2.6 Consolidation of Concrete . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
2.3 Steel Reinforcement, Anchor Bolts, and Miscellaneous Steel Items . . . . . . . . . . . . . . . 2-2
2.3.1 Steel Reinforcement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
2.3.2 Anchor Bolts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
2.3.3 Miscellaneous Steel Items . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
2.4 Form Materials and Form Ties. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
2.5 Reinforcement Installation Details . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
2.5.1 Support and Cover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
TABLE OF CONTENTS
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2.5.2 Location of Reinforcement in Walls. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
2.5.3 Lap Splices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
2.5.4 Development of Bars in Tension . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
2.5.5 Standard Hooks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
2.5.6 Webs of Waffle-Grid Walls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
2.5.7 Alternate Grade of Reinforcement and Spacing . . . . . . . . . . . . . . . . . . . . . . . . 2-3
2.6 Construction Joints in Walls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
2.7 Covering for Stay-in-Place Forms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
2.7.1 Interior Covering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
2.7.2 Exterior Wall Covering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
CHAPTER 3. FOOTINGS AND FOUNDATION WALLS . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
3.1 Footings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
3.1.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
3.1.2 Minimum Footing Size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
3.1.3 Seismic Design Categories D0, D1 and D2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
3.2 Foundation Wall Requirements – General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
3.2.1 Stem Walls with Slab-on-Ground . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2
3.2.2 Crawlspace Walls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2
3.2.3 Basement Walls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3
3.2.4 Requirements for Seismic Design Category C . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3
3.2.5 Requirements for Seismic Design Categories D0, D1 and D2 . . . . . . . . . . . . . . . 3-3
3.3 Location of Reinforcement in Wall . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3
3.4 Exterior Foundation Wall Coverings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3
3.5 Termite Protection Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3
CHAPTER 4. ABOVE-GRADE WALLS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1
4.1 Above-Grade Wall Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1
4.1.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1
4.1.2 Wall Reinforcement for Wind . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1
4.1.3 Wall Reinforcement for Seismic Design Categories C, D0, D1 and D2 . . . . . . . . 4-1
4.1.4 Concrete Strength for Seismic Design Categories D0, D1 and D2. . . . . . . . . . . . 4-1
4.1.5 Continuity of Wall Reinforcement Between Stories . . . . . . . . . . . . . . . . . . . . . . 4-2
4.1.6 Termination of Reinforcement. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2
4.1.7 Location of Reinforcement in Wall . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2
CHAPTER 5. SOLID WALLS FOR RESISTANCE TO LATERAL FORCES. . . . . . . . . . . . . . . 5-1
5.1 Length of Solid Wall . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
5.1.1 Length of Solid Wall for Wind . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
5.1.2 Length of Solid Wall for Seismic. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-2
5.2 Solid Wall Segments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3
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5.2.1 Minimum Length of Solid Wall Segment and Maximum Spacing . . . . . . . . . . . . 5-3
5.2.2 Reinforcement in Solid Wall Segments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3
5.2.3 Solid Wall Segments at Corners . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4
5.3 Minimum Wall Thickness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4
5.3.1 Seismic Design Categories A, B and C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4
5.3.2 Seismic Design Categories C, D0, D1 and D2 . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4
5.4 Common Wall Between Attached Garage and Dwelling . . . . . . . . . . . . . . . . . . . . . . . 5-4
CHAPTER 6. REQUIREMENTS FOR CONNECTIONS AND DIAPHRAGMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1
6.1 Connections – General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1
6.2 Foundation Wall-to-Footing Connection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1
6.3 Connections Between Concrete Walls and Light-Framed Floor, Ceiling and Roof Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-2
6.3.1 Anchor Bolts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-2
6.3.2 Removal of Stay-in-Place Form Material at Bolts . . . . . . . . . . . . . . . . . . . . . . . . 6-2
6.4 Connections Between Concrete Walls and Light-Framed Floor Systems . . . . . . . . . . . 6-2
6.5 Connections Between Concrete Walls and Light-Framed Ceiling and Roof Systems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-2
6.6 Floor, Roof and Ceiling Diaphragm Construction . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3
6.6.1 Floor diaphragm construction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3
6.6.2 Roof and Ceiling Diaphragm Construction . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3
6.6.3 Blocked Diaphragms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3
6.6.4 Diaphragm Continuous Ties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3
CHAPTER 7. REQUIREMENTS FOR LINTELS ANDREINFORCEMENT AROUND OPENINGS. . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1
7.1 Reinforcement Around Openings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1
7.1.1 Horizontal Reinforcement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1
7.1.2 Vertical Reinforcement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1
7.1.3 Wall Segments in Seismic Design Categories C, D0, D1 and D2 . . . . . . . . . . . . . 7-2
7.2 Lintels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-2
7.2.1 Lintels Designed for Gravity Load-Bearing Conditions . . . . . . . . . . . . . . . . . . . . 7-2
7.2.2 Lintels Designed for Uplift Loading Conditions . . . . . . . . . . . . . . . . . . . . . . . . . 7-2
7.2.3 Bundled Bars in Lintels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-3
7.2.4 Lintels Without Stirrups Designed for Non Load-Bearing Conditions . . . . . . . . . 7-3
7.2.5 Lintels in Seismic Design Categories C, D0, D1 and D2 . . . . . . . . . . . . . . . . . . . 7-3
APPENDIX A. ASD LOAD TABLES AND LOAD COMBINATIONS FOR CONCRETE WALL CONNECTIONS TO LIGHT-FRAMED FLOOR, CEILING AND ROOF SYSTEMS . . . . . . . . . . . . . . . . . . . . . . . . . . A-1
A.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1
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A.2 Detail 1 ASD Load Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1
Detail 1 ASD Load Combinations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1
A.3 Detail 2 ASD Load Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-7
Detail 2 ASD Load Combinations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-7
A.4 Detail 3 ASD Load Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-12
Detail 3 ASD Load Combinations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-12
APPENDIX B. LRFD LOAD TABLES AND LOAD COMBINATIONS FOR CONCRETE WALL CONNECTIONS TO LIGHT-FRAMED FLOOR, CEILING AND ROOF SYSTEMS . . . . . . . . . . . . . . . . . . . . . . . . . . B-1
B.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-1
B.2 Detail 1 LRFD Load Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-1
Detail 1 LRFD Load Combinations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-1
B.3 Detail 2 LRFD Load Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-5
Detail 2 LRFD Load Combinations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-5
B.4 Detail 3 LRFD Load Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-11
Detail 3 LRFD Load Combinations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-11
APPENDIX C. COMMENTARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-2
CHAPTER 1 COMMENTARY – General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-2
C1.1 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-2
C1.2 Limitations on Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-2
Building Geometry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-3
Site Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-3
Loads. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-4
C1.4 Forming System Limitations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-4
C1.5 Construction Documents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-4
C1.6 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-4
REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-4
CHAPTER 2 COMMENTARY – General Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . C-6
C2.1 Dimensions of Walls. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-6
C2.1.1 Flat Wall Systems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-6
C2.1.2 Waffle-Grid Wall Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-6
C2.1.3 Screen-Grid Wall Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-6
C2.2 Concrete . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-7
C2.2.3 Maximum Aggregate Size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-7
C2.2.4 Proportioning and Slump of Concrete . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-7
C2.2.5 Compressive Strength . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-8
C2.2.6 Consolidation of Concrete. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-8
C2.3.1 Steel Reinforcement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-8
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C2.3.2 Anchor Bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-8
C2.3.3 Miscellaneous Steel Items . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-8
C2.4 Form Materials and Form Ties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-8
C2.5.7 Alternate Grade of Reinforcement and Spacing. . . . . . . . . . . . . . . . . . . . . . . . C-9
C2.7 Covering for Stay-in-Place Forms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-9
C2.7.1 Interior Covering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-9
C2.7.2 Exterior Wall Covering. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-9
REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-9
CHAPTER 3 COMMENTARY – Footings and Foundation Walls . . . . . . . . . . . . . . . . . . . . . C-10
C3.1 Footings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-10
C3.1.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-10
C3.1.2 Minimum Footing Size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-10
C3.2 Foundation Wall Requirements – General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-11
C3.2.1 Stem Walls with Slab-on-Ground. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-12
C3.2.2 Crawlspace Walls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-13
C3.2.3 Basement Walls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-13
C3.3 Location of Reinforcement in Wall . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-14
C3.4 Exterior Foundation Wall Coverings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-14
C3.5 Termite Protection Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-14
REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-15
CHAPTER 4 COMMENTARY – Above-Grade Walls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-16
C4.1 Above-Grade Wall Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-16
C4.1.6 Termination of Reinforcement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-18
C4.1.7 Location of Reinforcement in Wall . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-18
REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-19
CHAPTER 5 COMMENTARY – Solid Walls for Resistance to Lateral Forces. . . . . . . . . . . . C-20
C5.1 Length of Solid Wall. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-20
C5.2 Solid Wall Segments. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-24
C5.2.2 Reinforcement in Solid Wall Segments. . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-24
REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-24
CHAPTER 6 COMMENTARY – Requirements for Connections and Diaphragms . . . . . . . . C-25
C6.2 Foundation Wall-to-Footing Connection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-25
C6.4 Connections Between Concrete Walls and Light-Framed Floor Systems . . . . . . . . . . C-25
C6.5 Connections Between Concrete Walls and Light-Framed Ceiling and Roof Systems . C-25
C6.6 Floor, Roof and Ceiling Diaphragm Construction . . . . . . . . . . . . . . . . . . . . . . . . . . . C-25
REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-26
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CHAPTER 7 COMMENTARY – Requirements for Lintels and Reinforcement Around Openings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-27
C7.1 Reinforcement Around Openings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-27
C7.1.2 Vertical Reinforcement. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-27
C7.2 Lintels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-28
C7.2.1 Lintels Designed for Gravity Load-Bearing Conditions . . . . . . . . . . . . . . . . . C-28
C7.2.2 Lintels Designed for Uplift Loading Conditions. . . . . . . . . . . . . . . . . . . . . . . C-30
C7.2.3 Bundled Bars in Lintels. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-31
C7.2.4 Lintels Without Stirrups Designed for Non Load-Bearing Conditions . . . . . . C-31
REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-32
APPENDIX D. DESIGN EXAMPLE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D-1
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Table 1.1. Applicability Limits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7
Table 2.1. Dimensional Requirements for Walls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-4
Table 2.2. Lap Splice and Tension Development Lengths . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-4
Table 2.3. Maximum Spacing For Alternate Bar Size and/or Alternate Grade of Steel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5
Table 3.1. Minimum Width of Concrete Footings for Concrete Walls . . . . . . . . . . . . . . . . . 3-4
Table 3.2. Required Tributary Weight of Slab-on-Ground for Anchorage of Stem Wall . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-6
Table 3.3. Tributary Weight Provided by Slab-on-Ground for Anchorage of Stem Wall . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-6
Table 3.4. Minimum Vertical Reinforcement for Concrete Crawlspace Walls. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-7
Table 3.5. Minimum Horizontal Reinforcement for Concrete Basement Walls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-7
Table 3.6. Minimum Vertical Reinforcement for 6-Inch (152 mm) Nominal Flat Concrete Basement Walls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-8
Table 3.7. Minimum Vertical Reinforcement for 8-Inch (203 mm) Nominal Flat Concrete Basement Walls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-9
Table 3.8. Minimum Vertical Reinforcement for 10-Inch (252 mm) Nominal Flat Concrete Basement Walls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-10
Table 3.9. Minimum Vertical Reinforcement for 6-Inch (152 mm) Waffle-Grid Basement Walls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-11
Table 3.10. Minimum Vertical Reinforcement for 8-Inch (203 mm) Waffle-Grid Basement Walls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-12
Table 3.11. Minimum Vertical Reinforcement for 6-Inch (152 mm) Screen-Grid Basement Walls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-13
Table 3.12. Minimum Vertical Reinforcement for 6-, 8-, 10- and 12-Inch Nominal Flat Basement Walls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-14
Table 4.1. Minimum Vertical Reinforcement for Flat Above-Grade Walls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4
Table 4.2. Minimum Vertical Reinforcement for Waffle-Grid Above-Grade Walls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-6
Table 4.3. Minimum Vertical Reinforcement for 6-inch Screen-Grid Above-Grade Walls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-7
Table 4.4. Minimum Vertical Reinforcement for Flat, Waffle- and Screen-Grid Stem Walls Designed Continuous With Above-Grade Walls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-8
Table 5.1A. Unadjusted Length of Solid Wall, TL, Required in Each Exterior Endwall for Wind Perpendicular to Ridge One Story or Top Story of Two-Story . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-6
LIST OF TABLES
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Table 5.1B. Unadjusted Length of Solid Wall, TL, Required in Each Exterior Endwall for Wind Perpendicular to RidgeFirst Story of Two-Story. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-8
Table 5.1C. Unadjusted Length of Solid Wall, TL, Required in Each Exterior Sidewall for Wind Parallel to Ridge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-9
Table 5.2. Reduction Factor, R5.2, for Buildings with Mean Roof Height Less than 35 Feet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-10
Table 5.3. Reduction Factor, R5.3, for Floor-to-Ceiling Wall Heights Less than 10 Feet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-11
Table 5.4A. Adjustment Factor, F, and Layout of Reinforcement at Each End of Solid Wall Segments for Flat Walls. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-12
Table 5.4B. Adjustment Factor, F, and Layout of Reinforcement at Each End of Solid Wall Segments forWaffle-Grid and Screen-Grid Walls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-14
Table 5.5A. Unadjusted Length of Solid Wall, TL, Required in Each Exterior Endwall and Sidewall for Seismic ResistanceOne Story or Top story of Two-Story . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-16
Table 5.5B. Unadjusted Length of Solid Wall, TL, Required in Each Exterior Endwall and Sidewall for Seismic ResistanceFirst Story of Two-Story. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-18
Table 5.5C. Unadjusted Length of Solid Wall, TL, Required in Each Exterior Endwall and Sidewall for Seismic ResistanceFirst Story of Two-Story with Second Story Exterior Walls of Light-Framed Construction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-19
Table 5.6A. Reduction Factor, R5.6, for Floor-to-Ceiling Wall Heights of Less than 10 Feet Second Story Exterior Walls of Concrete Construction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-20
Table 5.6B. Reduction Factor, R5.6, for Floor-to-Ceiling Wall Heights of Less than 10 Feet Second Story Exterior Walls of Light-Framed Construction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-21
Table 5.7. Reduction Factor, R5.7, for Exterior Wall Covering Weighing 3 psf or Less. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-22
Table 5.8. Reduction Factor, R5.8 , for Ground Snow Load Equal to 40 psf. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-23
Table 6.1. Maximum Nail Spacing for Wood Structural Panel Sheathing in Wood Framed Floor Diaphragms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-4
Table 6.2. Maximum Screw Spacing for Wood Structural Panel Sheathing in Cold-Formed Steel Framed Floor Diaphragms . . . . . . . . . . . . . . . . . . . . . . . . . 6-5
Table 6.3. Maximum Nail Spacing for Wood Structural Panel Sheathing in Wood Framed Roof and Ceiling Diaphragms . . . . . . . . . . . . . . . . . . . . . . . . . 6-6
Table 6.4. Maximum Screw Spacing for Wood Structural Panel Sheathingin Cold-Formed Steel Framed Roof and Ceiling Diaphragms . . . . . . . . . . . . . . . . . . . . . . . . 6-7
Table 7.1A. Factored Roof Uplift Force . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-4
Table 7.1B. Number, Size and Grade of Vertical Reinforcement on Each Side of Opening . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-4
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Table 7.2. Lintel Design Loading Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-5
Table 7.3. Maximum Allowable Clear Spans for 4-inch Nominal Thick Flat Lintels in Load-Bearing Walls Roof Clear Span 40 feet and Floor Clear Span 32 feet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-6
Table 7.4. Maximum Allowable Clear Spans for 4-inch Nominal Thick Flat Lintels in Load-Bearing Walls Roof Clear Span 32 feet and Floor Clear Span 24 feet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-8
Table 7.5. Maximum Allowable Clear Spans for 6-inch Nominal Thick Flat Lintels in Load-Bearing Walls Roof Clear Span 40 feet and Floor Clear Span 32 feet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-9
Table 7.6. Maximum Allowable Clear Spans for 6-inch Nominal Thick Flat Lintels in Load-Bearing Walls Roof Clear Span 32 feet and Floor Clear Span 24 feet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-10
Table 7.7. Maximum Allowable Clear Spans for 8-inch Nominal Thick Flat Lintels in Load-Bearing Walls Roof Clear Span 40 feet and Floor Clear Span 32 feet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-11
Table 7.8. Maximum Allowable Clear Spans for 8-inch Nominal Thick Flat Lintels in Load-Bearing Walls Roof Clear Span 32 feet and Floor Clear Span 24 feet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-12
Table 7.9. Maximum Allowable Clear Spans for 10-inch Nominal Thick Flat Lintels in Load-Bearing Walls Roof Clear Span 40 feet and Floor Clear Span 32 feet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-13
Table 7.10. Maximum Allowable Clear Spans for 10-inch Nominal Thick Flat Lintels in Load-Bearing Walls Roof Clear Span 32 feet and Floor Clear Span 24 feet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-14
Table 7.11. Maximum Allowable Clear Spans for 6-inch Thick Waffle-Grid Lintels in Load-Bearing Walls Maximum Roof Clear Span of 40 feet and Maximum Floor Clear Span of 32 feet . . . . . . . . . . . . . . . . 7-16
Table 7.12. Maximum Allowable Clear Spans for 6-inch Thick Waffle-Grid Lintels in Load-Bearing Walls Maximum Roof Clear Span of 32 feet and Maximum Floor Clear Span of 24 feet . . . . . . . . . . . . . . . . 7-18
Table 7.13. Maximum Allowable Clear Spans for 8-inch Thick Waffle-Grid Lintels in Load-Bearing Walls Maximum Roof Clear Span of 40 feet and Maximum Floor Clear Span of 32 feet . . . . . . . . . . . . . . . 7-19
Table 7.14. Maximum Allowable Clear Spans for 8-inch Thick Waffle-Grid Lintels in Load-Bearing Walls Maximum Roof Clear Span of 32 feet and Maximum Floor Clear Span of 24 feet . . . . . . . . . . . . . . . 7-20
Table 7.15. Maximum Allowable Clear Spans for 6-inch Thick Screen-Grid Lintels in Load-Bearing Walls Roof Clear Span 40 feet and Floor Clear Span 32 feet . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-21
Table 7.16. Maximum Allowable Clear Spans for 6-inch Thick Screen-Grid Lintels in Load-Bearing Walls Roof Clear Span 32 feet and Floor Clear Span 24 feet . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-22
Table 7.17. Maximum Allowable Clear Spans for Flat Lintels Without Stirrups in Non-Load-Bearing Walls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-23
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Table 7.18. Maximum Allowable Clear Spans for Waffle-Grid and Screen-Grid Lintels Without Stirrups in Non-Load-Bearing Walls . . . . . . . . . . . . . . . . . . . . . 7-24
Table 7.19. Maximum Allowable Clear Spans for 4-inch Nominal Thick Flat Lintels in Top Story Walls Subject to Roof Uplift Forces . . . . . . . . . . . . . . . . . . . . 7-26
Table 7.20. Maximum Allowable Clear Spans for 6-inch Nominal Thick Flat Lintels in Top Story Walls Subject to Roof Uplift Forces . . . . . . . . . . . . . . . . . . . . 7-28
Table 7.21. Maximum Allowable Clear Spans for 8-inch Nominal Thick Flat Lintels in Top Story Walls Subject to Roof Uplift Forces . . . . . . . . . . . . . . . . . . . . 7-29
Table 7.22. Maximum Allowable Clear Spans for 10-inch Nominal Thick Flat Lintels in Top Story Walls Subject to Roof Uplift Forces . . . . . . . . . . . . . . . . . . . . 7-30
Table 7.23. Maximum Allowable Clear Spans for 6-inch Thick Waffle-Grid Lintels in Top Story Walls Subject to Roof Uplift Forces. . . . . . . . . . . . . . . . . . . 7-32
Table 7.24. Maximum Allowable Clear Spans for 8-inch Thick Waffle-Grid Lintels in Top Story Walls Subject to Roof Uplift Forces. . . . . . . . . . . . . . . . . . . 7-34
Table 7.25. Maximum Allowable Clear Spans for 6-inch Thick Screen-Grid Lintels in Top Story Walls Subject to Roof Uplift Forces. . . . . . . . . . . . . . . . . . . 7-35
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Figure 1.1. One story garage attached to main building.. . . . . . . . . . . . . . . . . . . . . . . . . . . 1-8
Figure 1.2. Offset wall lines. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-8
Figure 1.3. Wall systems covered by this standard. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-9
Figure 2.1. Flat wall system requirements.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-6
Figure 2.2. Waffle-grid wall system requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-6
Figure 2.3. Screen-grid wall system requirements.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-7
Figure 2.4. Lap splice requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-7
Figure 2.5. Development length of reinforcement. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8
Figure 2.6. Standard hooks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8
Figure 3.1. Concrete stem wall with slab-on-ground construction. . . . . . . . . . . . . . . . . . . . 3-16
a. Stem wall not anchored to slab-on-ground . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-16
b. Stem wall anchored to slab-on-ground . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-16
Figure 3.2. Concrete crawlspace wall construction.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-17
Figure 3.3. Concrete basement wall construction.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-18
Figure 4.1. Concrete wall supporting roof. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-10
Figure 4.2. Concrete wall supporting light-framed second story wall and roof. . . . . . . . . . . 4-11
Figure 4.3. Concrete wall supporting concrete second story wall and roof. . . . . . . . . . . . . . 4-12
Figure 4.4. Monolithic slab-on-ground supporting concrete wall. . . . . . . . . . . . . . . . . . . . . 4-13
Figure 5.1. Reinforcement layout details at ends of solid wall segments for use with Tables 5.4A and B.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-24
Figure 5.2. Variables for use with equations in Sections 5.1.1 and 5.1.2. . . . . . . . . . . . . . . 5-25
Figure 6.1. Foundation wall-to-footing connection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-8
Figure 6.2. Development of vertical steel adjacent to openings in walls.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-9
Figure 6.3. Wood framed floor to side of concrete wall, framing perpendicular. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-10
Figure 6.3 Table. Wood Framed Floor to Side of Concrete Wall, Framing Perpendicular . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-11
Figure 6.4. Wood framed floor to side of concrete wall, framing parallel. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-12
Figure 6.4 Table. Wood Framed Floor to Side of Concrete Wall, Framing Parallel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-13
Figure 6.5. Wood framed floor to top of concrete wall, framing perpendicular. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-14
Figure 6.5 Table. Wood Framed Floor to Top of Concrete Wall, Framing Perpendicular . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-15
Figure 6.6. Wood framed floor to top of concrete wall, framing parallel. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-16
LIST OF FIGURES
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Figure 6.6 Table. Wood Framed Floor to Top of Concrete Wall, Framing Parallel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-17
Figure 6.7. Cold-formed steel floor to side of concrete wall, framing perpendicular. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-18
Figure 6.7 Table. Cold-Formed Steel Framed Floor to Side of Concrete Wall, Framing Perpendicular . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-19
Figure 6.8. Cold-formed steel floor to side of concrete wall, framing parallel. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-20
Figure 6.8 Table. Cold-Formed Steel Framed Floor to Side of Concrete Wall, Framing Parallel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-21
Figure 6.9. Cold-formed steel floor to top of concrete wall, framing perpendicular. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-22
Figure 6.9 Table. Cold-Formed Steel Framed Floor to Top of Concrete Wall, Framing Perpendicular . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-23
Figure 6.10. Cold-formed steel floor to top of concrete wall, framing parallel. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-24
Figure 6.10 Table. Cold-Formed Steel Framed Floor to Top of Concrete Wall, Framing Parallel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-25
Figure 6.11. Wood framed roof to top of concrete wall, framing perpendicular. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-26
Figure 6.11 Table. Wood Framed Roof to Top of Concrete Wall, Framing Perpendicular . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-27
Figure 6.12. Wood framed roof to top of concrete wall, framing parallel. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-28
Figure 6.12 Table. Wood Framed Roof to Top of Concrete Wall, Framing Parallel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-29
Figure 6.13. Cold-formed steel roof to top of concrete wall, framing perpendicular. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-30
Figure 6.13 Table. Cold-Formed Steel Framed Roof to Top of Concrete Wall, Framing Perpendicular . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-31
Figure 6.14. Cold-formed steel roof to top of concrete wall, framing parallel. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-32
Figure 6.14 Table. Cold-Formed Steel Framed Roof to Top of Concrete Wall, Framing Parallel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-33
Figure 7.1. Reinforcement around openings.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-36
Figure 7.2. Lintel and wall segment reinforcing for Seismic Design Categories C, D0, D1 and D2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-37
Figure 7.3. Flat lintel construction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-38
Figure 7.4. Waffle-grid lintel construction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-39
Figure 7.5. Screen-grid lintel construction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-40
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Chapter 1General
1.1 SCOPEThe provisions of this Standard apply to the design andconstruction of concrete footings, foundation walls andabove-grade walls, both load bearing and non-load bearing,for:
1. detached one- and two-family dwellings,
2. multiple dwellings, and
3. one-story buildings of other occupancy groups assignedto Seismic Design Category A,
each of which shall comply with the limitations of Section1.2. Concrete walls cast in removable forms and stay-in-place forms are covered.
This Standard is based on the assumption that interior wallsand partitions, both load bearing and non-load bearing,floors and roof/ceiling assemblies are constructed of light-framed construction complying with the limitations ofSection 1.2. Design and construction of light-framed assem-blies shall be in accordance with the applicable buildingcode. If there is no code, assemblies of wood frame con -struc tion shall be designed and constructed in accor dancewith AF&PA/WFCM, and assemblies of cold-formed steelframing shall be designed and constructed in accordancewith AISI/S230. Where second-story exterior walls are oflight-framed construction, they shall be designed andconstructed as required by the applicable building code, or inthe absence of a code the applicable standard cited above.
Buildings or portions thereof, including interior concretewalls, that are not within the scope of this Standard shall bedesigned and constructed in accordance with the applicablebuilding code. Aspects of concrete construction not specifi-cally addressed by this Standard shall comply with the applic-able building code. Where there is no code, the portion of
concrete construction shall be designed and constructed inaccordance with ACI 318 to meet the loading requirementsof ASCE 7.
1.2 LIMITATIONS ON USEBuildings and portions thereof constructed in accordancewith this Standard shall comply with the limitations of thissection and Table 1.1.
1.2.1 Flood Prone AreasThis Standard does not apply to buildings or portions thereofsubject to flood loads, including those built along the coastin hurricane-prone regions subjected to storm surge.
1.2.2 Seismic Design Categories C, D0, D1and D2
In addition to the limitations of this section and Table 1.1,multiple dwellings assigned to Seismic Design Category C,and all buildings assigned to Seismic Design Category D0, D1
or D2 shall be regular. To be considered regular, all of thefollowing conditions shall apply:
1. The building shall be rectangular with a maximumbuilding aspect ratio of 2:1. The building aspect ratio isthe longest plan dimension of the building divided by theshortest plan dimension of the building.
Exceptions:
1. An attached single-story garage of up to 625 squarefeet (58 m2) in area is permitted to be considered aseparate rectangle (see Figure 1.1) provided both ofthe following are satisfied:
a. Concrete walls conforming to this Standard areprovided on all four sides of the garage anddwelling, and
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b. In the concrete wall that is common to the garageand dwelling, the required length of solid wall shallbe the sum of the lengths determined for each,considered separately.
The aspect ratios of the garage and the dwelling, eachconsidered separately, shall not exceed 2:1. See Section5.4.
2. Portions of the exterior wall are permitted to extendup to 4 feet (1.2 m) beyond the main buildingrectangle (see Figure 1.2) provided all of the followingare satisfied:
a. Required lengths of solid wall without openings, asrequired by Section 5.1, do not occur in extendedwall portions,
b. Extended wall portions are continuous in one planefrom the foundation to the roof, and
c. Design is provided for chord members and theirconnections at the main building wall line (seeFigure 1.2).
2. Walls shall be aligned vertically with the walls below.
3. Cantilever and setback construction shall not bepermitted.
4. The total weight of interior and exterior finishes appliedor fastened to concrete walls shall not exceed 13 psf(0.62 kN/m2).
5. The gable portion of exterior walls that are otherwiseof concrete construction shall be of light-framedconstruction.
6. The floors and roof shall be laterally supported on alledges by shear walls.
7. The larger dimension of an opening in the floor or roofshall not exceed the smaller of 12 ft (3.7 m) or 50percent of the least floor dimension.
8. All portions of a floor shall be at the same level (i.e., novertical offset).
9. Shear walls shall be oriented in two directions and shallbe perpendicular to each other.
10. Shear walls within a story shall be constructed of thesame material (e.g., concrete).
A structure or portion thereof where one or more of theabove conditions is not met shall be deemed to be irregularand not within the scope of this Standard:
1.2.3 Seismic Design Category EThis Standard does not apply to buildings or portions thereofassigned to Seismic Design Category E (in near-fault seismichazard conditions).
1.2.4 Conflicting RequirementsWhere differences occur between provisions of this Standardand the applicable building code, the provisions of theapplicable code shall apply.
1.3 REQUIREMENTS FOR SEISMICDESIGN CATEGORY CIf the applicable building code requires detached one-andtwo-family dwellings assigned to Seismic Design Category Cto comply with seismic design provisions, the seismic require-ments of this Standard for multiple dwellings assigned toSeismic Design Category C shall apply.
1.4 FORMING SYSTEM LIMITATIONSThree types of wall systems are covered by this Standard:flat, waffle-grid, and screen-grid (see Figure 1.3). Any form -ing system that results in a wall with flat, parallel surfacesis permitted. Waffle-grid and screen-grid stay-in-place formsystems complying with the dimensional limit ations ofTable 2.1 (see Figures 2.2 and 2.3) are permitted. Other wallsystems, including those cast in stay-in-place form systemsnot in compliance with Table 2.1, shall be designed in accor-dance with the applicable building code.
1.5 CONSTRUCTION DOCUMENTSConstruction documents shall include information necessaryto determine if the proposed construction conforms to therequirements of this Standard, and the applicable buildingcode, if any.
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Chapter 1 – General
1.6 DEFINITIONS
Accepted Engineering Practice: An engineeringapproach that conforms with accepted principles, tests, tech-nical standards, and sound judgment.
Anchor Bolt: A headed bolt, or threaded rod with nutembedded in the concrete, used to connect a structuralmember of different material to a concrete member.
Approved: Acceptable to the building official or otherauthority having jurisdiction.
Attic: The unfinished space between the ceiling joists of thetop story and the roof rafters.
Authority Having Jurisdiction: The organization, polit-ical subdivision, office, or individual charged with the respon-sibility of administering and enforcing the provisions ofapplicable building codes.
Backfill: The soil that is placed adjacent to completedportions of a structure (e.g., basement wall, stem wall) withsuitable compaction and allowance for settlement.
Basement: That portion of a building that is partly orcompletely below grade. See “story above grade plane.”
Basic Wind Speed: Three-second gust wind speed at 33feet (10 m) above the ground in Exposure C. Wind speeds inthis document are given in units of miles per hour (mph) andmeters per second (m/s) by 3-second gust measurements inaccordance with ASCE 7.
Construction Joint: The surface where two successiveplacements of concrete meet, across which it may be desir-able to achieve bond and through which reinforcement maybe continuous.
Crawlspace Wall: A perimeter foundation wall 5 feet(1.5 m) or less in height that creates an under floor spacewhich is not habitable.
Dead Load: Forces resulting from the weight of walls,partitions, framing, floors, ceilings, roofs, and all otherpermanent construction entering into, and becoming part of,a building.
Deflection: Elastic movement of a loaded structuralmember or assembly (i.e., beam or wall).
Design Lateral Soil Load: The force per unit areaproduced by the soil on an adjacent structure such as a base-ment wall.
Enclosure Classifications: Used for the purpose ofdetermining internal wind pressure. Buildings are classified aspartially enclosed or enclosed as defined in the applicablebuilding code, or if there is no code as follows:
Enclosed Building: A building not complying with therequirements for a partially enclosed building.
Partially Enclosed Euilding: A building that complieswith both of the following:
1. the total area of openings in a wall that receives posi-tive external pressure exceeds the sum of the area ofopenings in the balance of the building envelope (wallsand roof) by more than 10%, and
2. the total area of openings in a wall that receives positive external pressure exceeds 4 sq. ft. (0.37 m2)or 1% of the area of the wall, whichever is smaller, andthe percentage of openings in the balance ofthe building envelope (walls and roof) does not ex ceed20%.
Endwall: The exterior walls of the building that are per -pendicular to the roof ridge. The length of an endwall isdesignated by W. See “sidewall.”
Exposure Categories: Reflects the effect of the groundsurface roughness on wind loads in accordance with ASCE 7.Exposure Category B includes urban and suburban areas,wooded areas or other terrain with numerous closely spacedobstructions having the size of single-family dwellings orlarger. Exposure Category C includes open terrain with scat-tered obstructions having heights generally less than 30 ft(9.1 m) and water surfaces in hurricane prone regions.Exposure D includes flat, unobstructed areas and watersurfaces outside hurricane-prone regions as defined in theapplicable building code, and if there is no code, as definedin ASCE 7.
Flame-Spread Index: The numerical value assigned to amaterial tested in accordance with ASTM E84.
Flat Wall: A solid concrete wall of uniform thickness. Referto Table 2.1 and Figures 1.3 and 2.1.
Floor Joist: A horizontal structural framing member thatsupports floor loads.
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Footing: A below-grade foundation component that trans-mits loads directly to the underlying soil or rock.
Form Tie: A mechanical connection in tension used toprevent concrete forms from spreading due to the fluid pres-sure of fresh concrete, and which remains permanentlyembedded in the concrete.
Foundation: The structural elements through which thedead load of a structure and the loads and forces imposedon it are transmitted to the footing, or directly to the soil orrock.
Foundation Wall: The structural element of a foundationthat resists lateral soil loads, if any, and transmits the deadload of a structure and the loads and forces imposed on it tothe footing, or directly to the soil or rock; includes basement,stem, and crawlspace walls.
Grade: The finished ground level adjoining the building atall exterior walls.
Grade Plane: A reference plane representing the averageof the finished ground level adjoining the building at all exte-rior walls.
Ground Snow Load: Measured load on the ground dueto snow accumulation developed from a statistical analysis ofweather records expected to be exceeded once every 50years at a given site.
Interpolation: A mathematical process used to computean intermediate value of a quantity between two givenvalues assuming a linear relationship.
Lap Splice: A connection of reinforcing steel made bylapping the ends of bars.
Lateral Load: A horizontal force, created by soil, wind, orearthquake, acting on a structure or its components.
Lateral Support: A horizontal member or assemblyproviding stability to a wall in the direction perpendicular tothe plane of the wall.
Ledger: A horizontal structural member fastened to theside of a wall to serve as a connection point for other struc-tural members, typically floor joists.
Light-Framed Construction: Construction where walls,floors and roofs are primarily formed by a system ofrepetitive wood or cold-formed steel framing members.
Lintel: A horizontal structural element of reinforcedconcrete located above an opening in a wall to support theconstruction and superimposed loads from above.
Live Load: Any gravity vertical load other than dead load,or environmental loads, such as from wind, snow, rain,earthquake, or flood.
Load-Bearing Value of Soil: The allowable load persurface area of soil. It is usually expressed in pounds persquare foot (psf) or kilonewtons per square meter (kN/m2).
Multiple Dwelling: A building with three or moreattached single-family dwelling units, including townhouses,where means of egress from each dwelling unit are indepen-dent.
Roof Snow Load: Uniform load on the roof due to snowaccumulation; typically 70 to 80 percent of the ground snowload in accordance with ASCE 7.
Screen-Grid Wall: A perforated concrete wall with closelyspaced vertical and horizontal concrete members (cores) withvoids in the concrete between the members created by thestay-in-place form. Refer to Table 2.1 and Figures 1.3 and2.3.
Seismic Force: The force exerted on a structure or portionthereof resulting from seismic (earthquake) ground motions.
Seismic Design Category: The classification assigned abuilding based on its use or occupancy and the severity ofthe design earthquake ground motion at the site. SeismicDesign Categories A, B, C, D0, D1, D2 and E correspond tosuccessively greater seismic design forces and detailingrequirements. Refer to the applicable building code andASCE 7.
Sidewall: The exterior walls of the building that are parallelto the roof ridge. The length of a sidewall is designated by L.See “endwall.”
Slab-on-Ground: A concrete slab, which is continuouslysupported by, and rests on, the soil directly below.
Slump: A measure of consistency of freshly mixed concreteequal to the subsidence of the molded specimen measuredimmediately after the removal of the slump cone.
Smoke-Developed Index: The numerical value assignedto a material tested in accordance with ASTM E84.
Span: The clear horizontal distance between supports.
Specified Compressive Strength of Concrete: Thecompressive strength of concrete, f'c, used in design andevaluated in accordance with Chapter 5 of ACI 318.
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Chapter 1 – General
Stay-in-Place Concrete Forms: A concrete formingsystem using stay-in-place forms of foam plastic insulation, acomposite of cement and foam insulation, a composite ofcement and wood chips, or other insulating material forconstructing cast-in-place concrete walls.
Stem Wall: A foundation wall supported directly by the soilor rock, or on a footing that supports an above-gradeconcrete wall and retains unbalanced backfill beneath theslab-on-ground of the first story above grade plane.
Stirrup: Steel bars, wires, or welded wire reinforcementgenerally oriented perpendicular to longitudinalreinforcement, properly anchored, and extending across thedepth of concrete beams, lintels, or similar members to resistshear and diagonal tension stresses in excess of thosepermitted to be carried by the concrete alone.
Story: That portion of the building included between theupper surface of any floor and the upper surface of the floornext above, except that the top-most story shall be from theupper surface of the top-most floor to the top of the ceilingjoists, or where there is no ceiling, to the top of the roofrafters.
Story Above Grade Plane: Any story with its finishedfloor surface entirely above grade plane except that a base-ment shall be considered as a story above grade plane wherethe finished surface of the floor above the basement is(a) more than 6 feet (1.8 m) above the grade plane, or(b) more than 12 feet (3.7 m) above the finished groundlevel at any point.
Unbalanced Backfill Height: The difference betweenthe interior and exterior finish ground level. Where aninterior concrete slab-on-ground is provided, the unbalancedbackfill height is the difference in height between the exte-rior finish ground level and the top of the slab. For a stemwall, the difference in height between the exterior finishground level and the underside of the slab-on-ground.
Unsupported Wall Height: Within a basement or crawl-space, the maximum clear vertical distance between theexterior finish ground level, or interior finish ground level ortop of finished floor, whichever is lower, and the finishedceiling or sill plate. In other stories, the maximum clearvertical distance from the top of the finished floor to thefinished ceiling or sill plate.
Vapor Retarder: A layer of material used to retard thetransmission of water vapor through a building wall or floor.
Waffle-Grid Wall: A solid concrete wall with closelyspaced vertical and horizontal concrete members (cores) witha concrete web between the members created by the stay-in-place form. Refer to Table 2.1 and Figures 1.3 and 2.2.The thicker vertical and horizontal concrete cores and thethinner concrete webs create the appearance of a breakfastwaffle. It is also called an uninterrupted-grid wall in otherpublications.
Wall, Loadbearing: A concrete wall that supports morethan 200 pounds per linear foot (2.92 kN/m) of vertical loadin addition to its own weight. The weight of the wallincludes any exterior and interior finishes attached to thewall, unless indicated otherwise.
Wall, Non-Loadbearing: A concrete wall that is not aloadbearing wall.
Web: A concrete wall segment, a minimum of 2 inches(51 mm) thick, that connects the vertical and horizontalconcrete members (cores) of a waffle-grid stay-in-place wallor lintel member.
Wind Force: The force or pressure exerted on a buildingstructure and its components resulting from wind. Windforces are typically expressed in pounds per square foot (psf)or kilonewtons per square meter (kN/m2).
1.7 REFERENCE STANDARDS
This section lists standards that are referenced in thisStandard. Each listing includes the promulgating agency’sname, and the title, designation and edition assigned to thestandard by the promulgating agency.
ACI 318 – Building Code Requirements for StructuralConcrete (ACI 318-05) and Commentary (ACI 318R-05).American Concrete Institute, Farmington Hills, Michigan.2004.
AF&PA/NDS – National Design Specification (NDS) forWood Construction with Commentary and NDS SupplementDesign Values for Wood Construction, ANSI/AF&PA NDS-2005. American Wood Council, American Forest & PaperAssociation, Washington, DC. 2005.
AF&PA/WFCM – Wood Frame Construction Manual(WFCM) for One- and Two-Family Dwellings, 2001 Edition.American Wood Council, American Forest & PaperAssociation, Washington, DC. 2001.
AISI/S100 – North American Specification for the Design ofCold-Formed Steel Structural Members, AISI S100-07,American Iron and Steel Institute, Washington, DC. 2007.
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AISI/S230 – Standard for Cold-Formed Steel Framing –Prescriptive Method for One and Two Family Dwellings, AISIS230-07, American Iron and Steel Institute, Washington, DC.2007.
ASCE 7 – Minimum Design Loads for Buildings and OtherStructures, including Supplement No. 1, ASCE/SEI 7-05.American Society of Civil Engineers, Reston, Virginia. 2005.
ASTM A36 – Standard Specification for Carbon StructuralSteel, ASTM A36/A36M-05. American Society for Testing andMaterials (ASTM), West Conshohocken, Pennsylvania. 2005.
ASTM A307 – Standard Specification for Carbon Steel Boltsand Studs, 60,000 PSI Tensile Strength, ASTM A307-04e1.American Society for Testing and Materials (ASTM), WestConshohocken, Pennsylvania. 2004.
ASTM A615 – Standard Specification for Deformed andPlain Carbon-Steel Bars for Concrete Reinforcement, ASTMA615/A615M-04b. American Society for Testing andMaterials (ASTM), West Conshohocken, Pennsylvania. 2004.
ASTM A653 – Standard Specification for Sheet Steel, ZincCoated (Galvanized) or Zinc-Iron Alloy-Coated (Galvannealed)by the Hot-Dip Process, ASTM A653/A653M-06a. AmericanSociety for Testing and Materials (ASTM), WestConshohocken, Pennsylvania. 2006.
ASTM A706 – Standard Specification for Low-Alloy SteelDeformed and Plain Bars for Concrete Reinforcement, ASTMA706/A706M-04b. American Society for Testing andMaterials (ASTM), West Conshohocken, Pennsylvania. 2004.
ASTM A792 – Standard Specification for Steel Sheet, 55%Aluminum-Zinc Alloy-Coated by the Hot-Dip Process, ASTMA792/A792M-06a. American Society for Testing andMaterials (ASTM), West Conshohocken, Pennsylvania. 2006.
ASTM A875 – Standard Specification for Steel Sheet, Zinc-5% Aluminum Alloy-Coated by the Hot-Dip Process, ASTMA875/A875M-06. American Society for Testing and Materials(ASTM), West Conshohocken, Pennsylvania. 2006.
ASTM A996 – Standard Specification for Rail-Steel andAxle-Steel Deformed Bars for Concrete Reinforcement, ASTMA996/A996M-04. American Society for Testing and Materials(ASTM), West Conshohocken, Pennsylvania. 2004.
ASTM C94 – Standard Specification for Ready-MixedConcrete, ASTM C94/C94M-04. American Society for Testingand Materials (ASTM), West Conshohocken, Pennsylvania.2004.
ASTM C143 – Standard Test Method for Slump ofHydraulic-Cement Concrete, ASTM C143/ C143M-05a.American Society for Testing and Materials (ASTM), WestConshohocken, Pennsylvania. 2005.
ASTM C685 – Standard Specification for Concrete Made byVolumetric Batching and Continuous Mixing, ASTMC685/C685M-01. American Society for Testing and Materials(ASTM), West Conshohocken, Pennsylvania. 2001.
ASTM E84 – Standard Test Method for Surface BurningCharacteristics of Building Materials, ASTM E84-07.American Society for Testing and Materials (ASTM), WestConshohocken, Pennsylvania. 2007.
ASTM E119 – Standard Test Method for Fire Tests ofBuilding Construction and Materials, ASTM E119-07.American Society for Testing and Materials (ASTM), WestConshohocken, Pennsylvania. 2007.
ASTM F1554 – Standard Specification for Anchor Bolts,Steel, 36, 55, and 105-ksi Yield Strength, ASTM F1554-04e1. American Society for Testing and Materials (ASTM),West Conshohocken, Pennsylvania. 2004.
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Chapter 1 – General
Table 1.1. Applicability Limits
Attribute Limitation
Site and Environmental Parameters
Basic Wind Speed 150 mph (67 m/s) 3-second gust – Exposure D
Ground Snow Load, Pg 70 psf (3.35 kN/m2)
Seismic Design Category A, B, C, D0, D1, and D2 (see limitations in Section 1.2.2)
Design Lateral Soil Load (foundation walls) 60 psf per foot of depth (9.43 kN/m2/m)
Load Bearing Value of Soil 1,500 – 4,000 psf (71.85 – 191.60 kN/m2)
Building – General
Number of Stories2 stories above grade plane plus a basement that is notdefined as a story above grade plane
Mean Roof Height 35 feet (10.7 m)
Maximum Building Plan Dimension 60 feet (18.3 m)
Wind Enclosure Classification Enclosed
Occupancy Category for seismic, snow and wind II
Seismic Importance Factor I = 1.0
Snow Importance Factor I ≤ 1.0
Wind Importance Factor I ≤ 1.0
Foundation Walls
Unbalanced Backfill Height 10 feet (3.1 m)
Walls
Unit Weight of ConcreteNormal weight concrete having a density of approximately150 pcf (23.55 kN/m3) – see Table 2.1
Wall Height (unsupported) 10 feet (3.1 m)
Interior and Exterior Finishes Applied or Fastened toConcrete Walls1 13 psf (0.62 kN/m2)
Exterior Light Framed Walls, including interior and exterior finishes 15 psf (0.72 kN/m2)
Dead Load Allowance for Interior Light-Framed Wallsincluding finishes
For computing the seismic weight of the building, 10 psf (0.48 kN/m2)
Floors
Floor Dead Load 10 psf (0.48 kN/m2)
First-Floor Live Load 40 psf (1.92 kN/m2)
Second-Floor Live Load (sleeping rooms) 30 psf (1.44 kN/m2)
Floor Clear Span (unsupported) 32 feet (9.8 m)
Roofs
Maximum Roof Slope 12:12 (45 degrees)
Roof Plus Ceiling Dead Load, including roof covering 15 psf (0.72 kN/m2)
Roof Snow Load (0.77Pg ) 54 psf (2.59 kN/m2)
Attic Floor Live Load 20 psf (0.96 kN/m2)
Roof Clear Span (unsupported) 40 feet (12.2 m)
Roof Overhang All E dges 2 feet (610 mm) horizontal projection beyond exterior wall1 Does not include masonry veneer supported by the footing. See Table 3.1.
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See Section 1.2.2
Figure 1.1. One story garage attached to main building.
Chord member at main wall lineat floor and roof. This member and connections shall resist diaphragmchord forces and gravity loads
18'-0" (5.5 m) plus 2 times wall thicknessmaximum permitted length of offset
4'-0" (1.2 m)maximumpermitted offset
See Section 1.2.2
Figure 1.2. Offset wall lines.
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Chapter 1 – General
Concrete
A
A
B
B
C
C
Verticalconcrete
cores
Horizontalconcrete
cores
Verticalconcrete
cores
Horizontalconcrete
cores
Form –stay-in-placeor removable
Form –generallystays in place
Form –generallystays in place
Concrete web
Voids in concrete
Section A-A
Isometric
Isometric
Isometric
Section B-B
Section C-C
(a) Flat Wall System
(b) Waffle-Grid Wall System
(c) Screen-Grid Wall System
Figure 1.3. Wall systems covered by this standard.
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Chapter 2General Requirements
2.1 DIMENSIONS OF WALLSConcrete walls constructed in accordance with this Standardshall comply with the shapes and minimum concrete cross-sectional dimensions required in this section. Other types offorming systems resulting in concrete walls not incompliance with this section shall be designed in accordancewith the applicable building code, or where there is no codein accordance with ACI 318.
2.1.1 Flat Wall SystemsFlat walls shall comply with Table 2.1 and Figure 2.1 andshall have a minimum nominal concrete thickness of 4 inches(102 mm) for crawlspace walls, 6 inches (152 mm) for base-ment walls, and 4 inches (102 mm) for above-grade walls.For multiple dwellings assigned to Seismic Design CategoryC and all buildings assigned to Seismic Design Category D0,D1 or D2, the minimum nominal thickness of above gradewalls shall be 6 inches (152 mm). See Chapter 5.
2.1.2 Waffle-Grid Wall SystemsWaffle-grid wall systems shall have a minimum nominalconcrete thickness of 6 inches (152 mm) for the horizontaland vertical concrete members (cores). The dimensions of thecores and web shall comply with the requirements of Table2.1 and Figure 2.2. The maximum weight of waffle-gridwalls shall comply with Table 2.1.
2.1.3 Screen-Grid Wall SystemScreen-grid wall systems shall have a minimum nominalconcrete thickness of 6 inches (152 mm) for the horizontaland vertical concrete members (cores). The dimensions of thecores shall comply with the requirements of Table 2.1 andFigure 2.3. The maximum weight of screen-grid walls shallcomply with Table 2.1.
2.2 CONCRETE
2.2.1 Concrete and Materials for ConcreteMaterials used in concrete, and the concrete itself shallconform to requirements of the applicable building code, orwhere there is no code shall conform to ACI 318.
2.2.2 Concrete Mixing and DeliveryMixing and delivery of concrete shall comply with the applic-able building code, or where there is no code shall be inaccordance with ASTM C94 or ASTM C685.
2.2.3 Maximum Aggregate SizeThe nominal maximum size of coarse aggregate shall notexceed one-fifth the narrowest distance between sides offorms, or three-fourths the clear spacing between reinforcingbars or between a bar and the side of the form.
Exception: When approved, these limitations shall notapply where removable forms are used and workabilityand methods of consolidation permit concrete to beplaced without honeycombs or voids.
2.2.4 Proportioning and Slump of ConcreteProportions of materials for concrete shall be established toprovide workability and consistency to permit concrete to beworked readily into forms and around reinforcement underconditions of placement to be employed, withoutsegregation or excessive bleeding. Slump of concrete placedin removable forms shall not exceed 6 inches (152 mm).
Exception: When approved, the slump is permitted toexceed 6 inches (152 mm) for concrete mixtures that areresistant to segregation, and are in accordance with theform manufacturer’s recommendations.
Slump of concrete placed in stay-in-place forms shall exceed6 inches (152 mm). Slump of concrete shall be determined inaccordance with ASTM C143.
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2.2.5 Compressive StrengthThe minimum specified compressive strength of concrete, f 'c,shall be 2,500 psi (17.2 MPa) at 28 days. For buildingsassigned to Seismic Design Category D0, D1 or D2, theminimum f 'c shall be 3,000 psi (20.7 MPa).
2.2.6 Consolidation of ConcreteConcrete shall be consolidated by suitable means duringplacement and shall be worked around embedded items andreinforcement and into corners of forms. Where inspectionof in-place hardened concrete is not possible, such as wallsconstructed with stay-in-place forms, concrete shall beconsolidated by internal vibration.
Exception: When approved, concrete mixtures withslumps equal to or greater than 8 inches (203 mm) thatare specifically designed for placement without internalvibration need not be internally vibrated.
2.3 STEEL REINFORCEMENT,ANCHOR BOLTS, ANDMISCELLANEOUS STEEL ITEMS
2.3.1 Steel Reinforcement Reinforcement shall comply with ASTM A615, ASTM A706,or ASTM A996. ASTM A996 bars produced from rail steelshall be Type R. In all buildings assigned to Seismic DesignCategory D0, D1 or D2, reinforcement shall comply withASTM A615 Grade 60 (420 MPa), provided the steelcomplies with Section 21.2.5 of ACI 318, or ASTM A706Grade 60 (420 MPa).
2.3.2 Anchor BoltsAnchor bolts for use with connection details in accordancewith Figures 6.3 through 6.14 shall be bolts with headscomplying with ASTM A307 or ASTM F1554. ASTM A307bolts shall be Grade A (i.e., with heads). ASTM F1554 boltsfor use in multiple dwellings assigned to Seismic DesignCategory C, and all buildings assigned to Seismic DesignCategory D0, D1 or D2 shall be Grade 36. ASTM F1554 boltsfor use in buildings assigned to Seismic Design Category Aor B and in detached one-and two-family dwellings assignedto Seismic Design Category C shall be Grade 36 minimum.In lieu of using bolts with heads, it is permissible to use rodswith threads on both ends fabricated from steel complyingwith ASTM A36. The threaded end of the rod to be embeddedin the concrete shall be provided with a hex or square nut.
2.3.3 Miscellaneous Steel ItemsAngles, tension tie straps and continuous ties for use withconnection details in accordance with Figures 6.3 through
6.14 shall be fabricated from sheet steel complying withASTM A653 SS, ASTM A792 SS, or ASTM A875 SS. The steelshall be minimum Grade 33 unless a higher grade is requiredby the applicable figure.
2.4 FORM MATERIALS AND FORMTIESForms shall be made of wood, steel, aluminum, plastic, acomposite of cement and foam insulation, a composite ofcement and wood chips, or other approved material suitablefor supporting and containing concrete. Forms shall providesufficient strength to contain concrete during the concreteplacement operation.
The flame-spread index of stay-in-place forms made withfoam plastic shall not exceed 75 and the smoke-developedindex shall not exceed 450, where tested in accordance withASTM E84. The flame-spread index of stay-in-place formsmade with other materials shall comply with the applicablebuilding code, and if there is no code, the flame spreadindex shall not exceed 200 and the smoke-developed indexshall not exceed 450, where tested in accordance withASTM E84.
Form ties shall be steel, solid plastic, foam plastic, a com -posite of cement and wood chips, a composite of cementand foam plastic, or other suitable material capable of re -sisting the forces created by fluid pressure of fresh concrete.
2.5 REINFORCEMENT INSTALLATIONDETAILS
2.5.1 Support and CoverReinforcement shall be secured in the proper location in theforms with tie wire or other bar support system such thatdisplacement will not occur during the concrete placementoperation. Steel reinforcement in concrete cast against theearth shall have a minimum cover of 3 in. (75 mm). Mini -mum cover for reinforcement in concrete cast in removableforms that will be exposed to the earth or weather shall be11⁄2 in. (38 mm) for No. 5 bars and smaller, and 2 in. (50mm) for No. 6 bars and larger. For concrete cast in remov -able forms that will not be exposed to the earth or weather,and for concrete cast in stay-in-place forms, minimum covershall be 3⁄4-inch (19 mm). The minus tolerance for cover shallnot exceed the smaller of one-third the required cover and3⁄8-inch (10 mm).
2.5.2 Location of Reinforcement in WallsFor location of reinforcement in below-grade walls andabove-grade walls, see Sections 3.3 and 4.1.7, respectively.
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2.5.3 Lap SplicesVertical and horizontal wall reinforcement required byChapters 3, 4, and 5 shall be the longest lengths practical.Where splices are necessary in reinforcement, the length oflap splice shall be in accordance with Table 2.2 and Figure2.4. The maximum gap between noncontact parallel bars ata lap splice shall not exceed the smaller of one-fifth therequired lap length and 6 inches (150 mm). See Figure 2.4.
2.5.4 Development of Bars in TensionWhere bars are required to be developed in tension by otherprovisions of this Standard, development lengths shall com -ply with Table 2.2 and Figure 2.5. The development lengthsshown in Table 2.2 also apply to bundled bars in lintelsinstalled in accordance with Section 7.2.2.
2.5.5 Standard HooksWhere reinforcement is required by this standard to termi -nate with a standard hook, the hook shall comply withFigure 2.6.
2.5.6 Webs of Waffle-Grid WallsReinforcement, including stirrups, shall not be placed inwebs of waffle-grid walls, including lintels. Webs arepermitted to have form ties.
2.5.7 Alternate Grade of Reinforcement andSpacingWhere tables in Chapters 3 and 4 of this Standard specifyvertical wall reinforcement based on minimum bar size andmaximum spacing, which are based on Grade 60 steel rein-forcement, different size bars and/or bars made from adifferent grade of steel are permitted provided an equivalentarea of steel per linear foot of wall is provided. Table 2.3 ispermitted to be used to determine the maximum bar spacingfor different bar sizes than specified in the tables and/or barsmade from a different grade of steel. Bars shall not bespaced less than one-half the wall thickness, or more than48 inches (1.2 m) on center, or as indicated in Section 4.1.3.For buildings assigned to Seismic Design Category D0, D1 orD2, reinforcement shall comply with Section 2.3.1.
2.6 CONSTRUCTION JOINTS IN WALLS Construction joints shall be made and located so as not toimpair the strength of the wall. Construction joints in plainconcrete walls shall be located at points of lateral support,and a minimum of one No. 4 bar shall extend across theconstruction joint at a spacing not to exceed 24 inches(610 mm) on center. Construction joint reinforcement shall
have a minimum of 12 inches (305 mm) embedment onboth sides of the joint. Construction joints in reinforcedconcrete walls shall be located in the middle third of thespan between lateral supports, or located and constructedas required for joints in plain concrete walls.
Exception: Vertical wall reinforcement required by thisStandard is permitted to be used in lieu of constructionjoint reinforcement, provided the spacing does not exceed24 inches (610 mm), or the combination of wall reinforce -ment and No. 4 bars described above does not exceed24 inches (610 mm).
2.7 COVERING FOR STAY-IN-PLACEFORMS
2.7.1 Interior CoveringStay-in-place forms constructed of rigid foam plastic shall beprotected on the interior of the building as required by theapplicable building code. In the absence of a code, rigidfoam plastic that remains in place on the interior of thebuilding, including attic and crawl spaces, shall be coveredwith a minimum of 1⁄2-inch (13 mm) gypsum board or anapproved finish material that provides a thermal barrier tolimit the average temperature rise of the unexposed surfaceto no more than 250 degrees F (139 degrees C) after15 minutes of fire exposure in accordance with ASTM E119.The gypsum board shall be installed with a mechanicalfastening system. Adhesives are permitted to be used inaddition to mechanical fasteners.
2.7.2 Exterior Wall CoveringStay-in-place forms constructed of rigid foam plastics shallbe protected from sunlight and physical damage by theappli cation of an approved exterior wall covering complyingwith the requirements of the applicable building code. Exte -rior surfaces of other stay-in-place forming systems shall beprotected in accordance with the applicable building code.
For foundation wall waterproofing and dampproofing, seeSection 3.4.
Chapter 2 – General Requirements
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Table 2.1. Dimensional Requirements for Walls1,2
Wall type andnominal thickness
Wall groupnumber8
Maximumwallweight3
(psf)
Minimumwidth, W,of verticalcores (in.)
Minimumthickness,T,of verticalcores (in.)
Maximumspacing ofverticalcores (in.)
Maximumspacing ofhorizontalcores (in.)
Minimumweb thickness(in.)
4” Flat4 1 50 N/A N/A N/A N/A N/A6” Flat4 2 75 N/A N/A N/A N/A N/A8” Flat4 3 100 N/A N/A N/A N/A N/A10” Flat4 4 125 N/A N/A N/A N/A N/A6” Waffle-Grid 1 56 85 5.55 12 16 28” Waffle-Grid 2 76 86 86 12 16 26” Screen-Grid 1 53 6.257 6.257 12 12 N/A
For Sl: 1 inch = 25.4 mm; 1 psf = 0.0479 kN/m2
1 Width “W”, thickness “T”, spacing and web thickness, refer to Figures 2.2 and 2.3.2 N/A indicates not applicable3 Wall weight is based on a unit weight of concrete of 150 pcf (23.55 kN/m3). For flat walls the weight is based on the nominal thickness. In
multiple dwellings assigned to Seismic Design Category C, and all building assigned to Seismic Design Category D0, D1 or D2, the weight ofconcrete per unit area of waffle- and screen-grid walls shall not exceed the value indicated by more than 6%. The tabulated values do notinclude any allowance for interior and exterior finishes.
4 Nominal wall thickness. The actual as-built thickness of a flat wall shall not be more than 1⁄2-inch (13 mm) less or more than 1⁄4-inch (6 mm)more than the nominal dimension indicated.
5 Vertical core is assumed to be elliptical-shaped. Another shape core is permitted provided the minimum thickness is 5 inches (127 mm), themoment of inertia, I, about the centerline of the wall (ignoring the web) is not less than 65 in.4 (2.706 x 107 mm4), and the area, A, is not lessthan 31.25 in.2 (20,161 mm2). The width used to calculate A and I shall not exceed 8 inches (203 mm).
6 Vertical core is assumed to be circular. Another shape core is permitted provided the minimum thickness is 7 inches (178 mm), the moment ofinertia, I, about the centerline of the wall (ignoring the web) is not less than 200 in.4 (8.325 x 107 mm4), and the area, A, is not less than 49 in.2(31,613 mm2). The width used to calculate A and I shall not exceed 8 inches (203 mm).
7 Vertical core is assumed to be circular. Another shape core is permitted provided the minimum thickness is 5.5 inches (140 mm), the momentof inertia, I, about the centerline of the wall is not less than 76 in.4 (3.163 x 107 mm4), and the area, A, is not less than 30.25 in.2 (19,516 mm2).The width used to calculate A and I shall not exceed 6.25 inches (159 mm).
8 For purposes of design, in some cases in this Standard two or more walls have been grouped.
Table 2.2. Lap Splice and Tension Development Lengths
Bar sizeNo.
Yield strength of steel, fy psi (MPa)40,000 (280) 60,000 (420)
Splice length or tensiondevelopment length – in.
Lap splice length – tension4 20 305 25 386 30 45
Tension development length for straight bar4 15 235 19 286 23 34
Tension development length for:a 90° and 180° standard hooks with not less than 21⁄2 inches
(64 mm) of side cover perpendicular to plane of hook, andb 90° standard hooks with not less than 2 inches (51 mm) of
cover on the bar extension beyond the hook
4 6 9
5 7 11
6 8 13
Tension development length for bar with 90° or 180° standardhook having less cover than required above
4 8 125 10 156 12 18
1. For Sl: 1 inch = 25.4 mm
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Bar spacingfrom
applicabletable in
Chapter 3or 4 – in.
Maximum spacing for alternate bar size and/or alternate grade of steel – in.Bar size from applicable table in Chapter 3 or Chapter 4
No. 4 No. 5 No. 6Alternate bar size and/or alternate grade of steel desired to be used
Grade 60 Grade 40 Grade 60 Grade 40 Grade 60 Grade 40No. 5 No. 6 No. 4 No. 5 No. 6 No. 4 No. 6 No. 4 No. 5 No. 6 No. 4 No. 5 No. 4 No. 5 No. 6
8
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15
15
15
16
17
18
19
20
21
5
6
7
7
8
9
9
10
11
11
12
13
13
14
15
15
16
17
17
18
19
19
20
21
21
22
23
23
24
25
27
28
29
31
32
8
9
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
26
27
28
29
30
31
32
33
34
36
38
40
42
44
45
4
4
5
5
5
6
6
7
7
8
8
9
9
10
10
10
11
11
12
12
13
13
14
14
15
15
15
16
16
17
18
19
20
21
22
6
6
7
8
8
9
10
11
11
12
13
13
14
15
16
16
17
18
18
19
20
20
21
22
23
23
24
25
25
27
28
30
31
32
34
2
3
3
3
4
4
4
5
5
5
5
6
6
6
7
7
7
8
8
8
8
9
9
9
10
10
10
11
11
12
12
13
13
14
15
4
4
5
5
6
6
7
7
8
8
8
9
9
10
10
11
11
12
12
13
13
14
14
15
15
16
16
16
17
18
19
20
21
22
23
5
6
7
7
8
9
9
10
11
11
12
13
13
14
15
15
16
17
17
18
19
19
20
21
21
22
23
23
24
25
27
28
29
31
32
Table 2.3. Maximum Spacing For Alternate Bar Size and/or Alternate Grade of Steel1,2,3,4
For Sl: 1 inch = 25.4 mm1 This table is for use with tables in Chapters 3 and 4 that specify the minimum bar size and maximum spacing of vertical wall reinforcement
for foundation walls and above-grade walls. Reinforcement specified in tables in Chapters 3 and 4 is based on Grade 60 (420 MPa) steel rein-forcement.
2 Bar spacing shall not exceed 48 inches (1.2 m) on center and shall not be less than one-half the nominal wall thickness. See Note 3.3 In multiple dwellings assigned to Seismic Design Category C and all buildings assigned to Seismic Design Category D0, D1 or D2, the
maximum spacing of vertical wall reinforcement shall not exceed the dimensions indicated in Section 4.1.3.4 For Grade 50 (350 MPa) steel bars (ASTM A 996, Type R), use spacing for Grade 40 (280 MPa) bars or interpolate between Grade 40 (280
MPa) and Grade 60 (420 MPa).5 For intermediate bar spacings, use spacings based on lower value, or determine by interpolation.
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Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
2-6
Concrete
Form –stay-in-placeor removable
Vertical wall reinforcementas required
Concrete wallthickness
Plan View
See Table 2.1 for minimum dimensions.
Figure 2.1. Flat wall system requirements.
12"
(305
mm
)
max
imum
Form –generally staysin place
Horizontal concrete core(hidden) at maximum, 16 in.(406 mm) on center
Vertical concrete core
W
wid
thm
inim
um
T
thicknessminimum
Vertical wallreinforcement as required
2" (51 mm) minimum concrete web thickness
See Table 2.1 for minimum dimensions.
Plan View
Figure 2.2. Waffle-grid wall system requirements.
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2-7
Chapter 2 – General Requirements
12"
(305
mm
)
max
imum
T
thicknessminimum
Form –generallystays in place
Horizontal concrete core(hidden) at maximum, 12 in.(305 mm) on center
Vertical concrete core
W
wid
thm
inim
um
Vertical wallreinforcement as required
See Table 2.1 for minimum dimensions.
Plan View
Figure 2.3. Screen-grid wall system requirements.
db
Gap shall not exceed thesmaller of 1/5 lap lengthand 6 in. (152 mm)
Reinforcement as required
Reinforcement as required
Lap splice length – see Table 2.2
Note: Bars are permitted to be incontact with each other.
Concrete
Figure 2.4. Lap splice requirements.
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Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
2-8
Side coverfor 90° and180° hookper Table 2.2
Section A-ACover on barextension for 90° hookper Table 2.2
Dev
elop
men
t len
gth
per
Tab
le 2
.2
A
A
Sur
face
of c
oncr
ete
orse
ctio
n fr
om w
hich
dev
elop
men
tle
ngth
is m
easu
red
Figure 2.5. Development length of reinforcement.
db
db
6 db Benddiameter
6 db Benddiameter
12 d
b
Ext
ensi
on
21/2" (64 mm), but notless than 4 db extension
90° Hook
180° Hook
db
4 db Benddiameter
6 db Extension
db
4 db Benddiameter
6 d b Exte
nsion
90° Hook
135° Hook
Hooks for Reinforcement inWalls and Foundations
Hooks for Stirrups in Lintels andTies in Solid Wall Segments
Figure 2.6. Standard hooks.
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3-1
Chapter 3Footings and Foundation Walls
3.1 FOOTINGS
3.1.1 GeneralExcept where erected on solid rock or otherwise protectedfrom frost, the bottoms of footings shall extend below thefrost line as specified in the applicable building code. In nocase shall the bottom of exterior wall footings be less than12 inches (305 mm) below undisturbed ground. Footingsshall be supported on solid rock, undisturbed natural soil orapproved structural fill. Footings shall be stepped where it isnecessary to change the elevation of the top surface of thefooting, or where the slope of the bottom surface of thefooting will exceed 10%.
Footings to be constructed on soil with a bearing value ofless than 1,500 psf (71.85 kN/m2); on compressible, shifting,expansive, or other unknown characteristics; or on or near aslope steeper than 331⁄3%, shall comply with the applicablebuilding code. Where there is no code, footings to bear onsuch soils shall be designed and constructed in accordancewith accepted engineering practice and ACI 318.
3.1.2 Minimum Footing SizeMinimum sizes of concrete footings, including footings thatare monolithic with a slab-on-ground (see Figure 4.4), shallbe as set forth in Table 3.1. The allowable load bearing valueof soil for use in Table 3.1 shall be determined in accordancewith the applicable building code, or accepted engineeringpractice where there is no code. All other aspects of thedesign and construction of footings shall comply with theapplicable building code, or with accepted engineering prac-tice where there is no code.
3.1.3 Seismic Design Categories D0, D1 and D2
In buildings assigned to Seismic Design Category D0, D1 orD2, footings that are monolithic with slabs-on-ground shall
be provided with one No. 4 bar in the top and bottom ofthe footing in accordance with Figure 4.4. The bars shall belocated as close to the top and bottom of the footing asthe cover requirements of Section 2.5.1 will permit.
3.2 FOUNDATION WALLREQUIREMENTS – GENERALConcrete foundation walls shall be supported on continuousconcrete footings, including footings that are monolithicwith a slab-on-ground (see Figure 4.4), or other approvedsystems of sufficient design to safely transmit the loadsimposed directly to the soil. The minimum thickness of foun-dation walls and reinforcement, shall be as set forth in theappropriate table in this chapter. Where the wall or buildingis not within the limitations of Table 1.1; design is requiredby the tables in this chapter; or the wall is not within thescope of the tables in this chapter, the wall shall be designedin accordance with the applicable building code, or wherethere is no code in accordance with ACI 318. Foundationwalls with corbels, brackets or other projections built intothe wall for support of masonry veneer or other purposes arenot within the scope of the tables in this chapter. The thick-ness of foundations walls shall be equal to or greater thanthe thickness of the wall in the story above.
Where a foundation wall is reduced in thickness to provide ashelf for the support of masonry veneer, the reducedthickness shall be equal to or greater than the thickness ofthe wall in the story above. Vertical reinforcement for thefoundation wall shall be based on Table 3.12 and located inthe wall as required by Section 3.3 where that table is used.Vertical reinforcement shall be based on the thickness of thethinner portion of the wall.
Exception: Where the height of the reduced thicknessportion measured to the underside of the floor assembly
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Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
3-2
above is less than or equal to 24 inches (610 mm) and thereduction in thickness does not exceed 4 inches (102mm), the vertical reinforcement is permitted to be basedon the thicker portion of the wall.
Reinforcement around openings shall be provided in accor -dance with Chapter 7. One No. 4 vertical bar shall be placedin each corner of exterior walls.
3.2.1 Stem Walls with Slab-on-GroundStem walls that support above-grade walls shall be designedand constructed in accordance with this section and Figure3.1. Horizontal reinforcement for stem walls shall be inaccordance with Chapter 4 for above-grade walls.
3.2.1.1 Stem Walls Not Laterally Supported at Top
Concrete stem walls that are not monolithic with slabs-on-ground or are not otherwise laterally supported by slabs-on-grade shall comply with this section (see Figure 3.1a). Wherethe height of the stem wall from the exterior finish groundlevel to the top of the slab-on-ground is less than or equal to18 inches (457 mm), vertical reinforcement shall be providedin accordance with Chapter 4 and Table 4.1, 4.2 or 4.3 forabove-grade walls. Where the height of the stem wall fromthe exterior finish ground level to the top of the slab-on-ground is greater than 18 inches (457 mm), vertical rein -force ment shall be provided in accordance with Chapter 4and Table 4.4 for stem walls constructed continuous withabove-grade walls.
3.2.1.2 Stem Walls Laterally Supported at Top
Concrete stem walls that are monolithic with slabs-on-groundor are otherwise laterally supported by slabs-on-ground shallhave vertical reinforcement in accordance with Chapter 4and Table 4.1, 4.2 or 4.3 for above-grade walls (see Figure3.1b). The minimum nominal thickness of stem walls and theabove-grade walls they support shall be 6 inches (152 mm).The top of the stem wall shall be anchored to the slabwith minimum Grade 40 (280 MPa) No. 4 bars. Where therequired factored tributary weight from Table 3.2 is greaterthan 900 plf (13.1 kN/m), the spacing of anchor bars shallnot exceed 27 inches (686 mm). Where the required factoredtributary weight from Table 3.2 is less than or equal to 900plf (13.1 kN/m), the spacing shall not exceed 48 inches(1.22 m) on center. For required factored tributary weightsgreater than 900 plf (13.1 kN/m) and less than or equal to1,543 plf (22.5 kN/m), the spacing is permitted to be deter-mined by interpolating between 48 inches (1.22 m) and27 inches (686 mm). The end of the anchor bar embeddedin the wall shall terminate in a standard hook complying
with Section 2.5.5, and the hook shall engage a continuousminimum Grade 40 (280 MPa) No. 4 horizontal bar in thewall. The anchor bar shall extend into the wall as far as theminimum cover requirements to the outside of the wall ofSection 2.5.4 will permit. The anchor bar shall extend intothe slab-on-ground far enough to develop the bar in tensionin accordance with Section 2.5.4 and Figure 2.5.
The dimension of the slab-on-ground perpendicular to thestem wall and its thickness shall be sufficient to provide atributary weight based on Table 3.3 that is equal to orgreater than the required tributary weight indicated in Table3.2. The portion of the slab providing the tributary weightshall have minimum Grade 40 (280 MPa) No. 3 bars at nomore than 18 inches (457 mm) on center each way, or 6 x 6– W1.4 x W1.4 (152 x 152 – MW9 x MW9) welded wirereinforcement. The reinforcement shall be located at approxi-mately the center of the slab thickness. The reinforcementshall extend from the edge of the slab at the wall into theslab not less than the distance required by Table 3.3. Wherewelded wire reinforcement is used, a cross wire shall belocated a distance from the face of the wall equal to orgreater than the dimension required by Table 3.3. Within theportion of the slab required to provide the tributary weight,lap splices of bars shall comply with Section 2.5.3. Lapsplices of welded wire reinforcement shall be accomplishedby over-lapping the sheets so that the distance between theoutermost cross wires of each overlapped sheet of reinforce-ment is not less than the spacing between cross wires plus 2inches (51 mm). The portion of the slab that is required toprovide the tributary weight is permitted to have contraction(control) joints, construction joints, or both, provided all therequired reinforcement is continued through the joints.
3.2.2 Crawlspace WallsConcrete walls enclosing crawlspaces shall be constructed inaccordance with Figure 3.2 and shall be laterally supportedat the top and bottom of the wall in accordance withChapter 6. A wall enclosing a crawl space and having anunsupported height of more than 5 feet (1.5 m), or support -ing more than 4 feet (1.2 m) of unbalanced backfill shall bedesigned and constructed as a basement wall. A minimumof one continuous horizontal Grade 40 (280 MPa) No. 4 barshall be placed within 12 inches (305 mm) of the top of thecrawlspace wall. For crawlspace walls supporting above-grade concrete walls, horizontal reinforcement shall beprovided as required by Chapter 4 for the above-grade wall.Vertical wall reinforcement shall be provided in accordancewith Table 3.4. For crawlspace walls supporting above-gradewalls, vertical reinforcement shall be the greater of that re -quired by Table 3.4 or by Chapter 4 for the above-grade wall.
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3-3
Chapter 3 – Footings and Foundation Walls
3.2.3 Basement WallsConcrete basement walls shall be constructed in accordancewith Figure 3.3 and shall be laterally supported in the out-of-plane direction at the top and bottom of the wall inaccordance with Chapter 6. Horizontal wall reinforcementshall be provided in accordance with Table 3.5. For basementwalls supporting above-grade concrete walls, horizontal rein-forcement shall be the greater of that required by Table 3.5,or by Chapter 4 for the above-grade wall. Vertical wall rein-forcement shall be provided in accordance with Tables 3.6through 3.11. Vertical reinforcement for flat basement wallsretaining 4 feet (1.2 m) or more of unbalanced backfill ispermitted to be determined in accordance with Table 3.12.For basement walls supporting above-grade concrete walls,vertical reinforcement shall be the greater of that required byTables 3.6 through 3.12 or by Chapter 4 for the above-gradewall.
3.2.4 Requirements for Seismic DesignCategory CConcrete crawlspace and basement walls supporting above-grade concrete walls in multiple dwellings assigned toSeismic Design Category C shall be reinforced horizontallyand vertically with Grade 40 (280 MPa) No. 5 bars at amaximum spacing of 24 inches (610 mm) or Grade 40(280 MPa) No. 4 bars at a maximum spacing of 16 inches(406 mm) on center. The maximum spacing of vertical rein-forcement shall not exceed that permitted by Table 3.4, orTables 3.6 through 3.12. See Section 4.1.3.
3.2.5 Requirements for Seismic DesignCategories D0, D1, and D2
Concrete crawlspace and foundation walls supporting abovegrade concrete walls in buildings assigned to Seismic DesignCategory D0, D1 or D2 shall be reinforced horizontally andvertically with minimum Grade 60 (320 MPa) No. 5 bars at amaximum spacing of 18 inches (457 mm) or Grade 60 (320MPa) No. 4 bars at a maximum spacing of 12 inches (305mm) on center. The maximum spacing of verticalreinforcement shall not exceed that permitted by Table 3.4,or Tables 3.6 through 3.12. Vertical reinforcement shall becontinuous with above-grade concrete wall vertical reinforce-ment. Alternatively, the reinforcement shall extend into theabove-grade wall far enough to be lap-spliced with theabove-grade wall reinforcement in accordance withSection 2.5.3, or shall extend into the above-grade wall farenough to develop the bar in tension in accordance withSection 2.5.4.
In buildings assigned to Seismic Design Category D0, D1 orD2, the minimum specified compressive strength of concreteshall be 3,000 psi (20.5 MPa).
3.3 LOCATION OF REINFORCEMENTIN WALLThe center of vertical reinforcement in basement walls deter-mined from Tables 3.6 through 3.11, and in crawlspace wallsand stem walls shall be located at the centerline of the wall.Vertical reinforcement in basement walls determined fromTable 3.12 shall be located to provide a cover of 1.25 inches(32 mm) measured from the inside face of the wall. Regard -less of the table used to determine vertical wall reinforcement,the center of the steel shall not vary from the specified loca-tion by more than the greater of 10% of the wall thicknessand 3/8-inch (10 mm). Horizontal and vertical reinforcementshall be located in foundation walls to provide the minimumcover required by Section 2.5.1.
3.4 EXTERIOR FOUNDATION WALLCOVERINGSStay-in-place forms constructed of rigid foam plastics shallbe protected from sunlight and physical damage by theapplication of an approved exterior wall covering complyingwith the requirements of the applicable building code.
Concrete foundation walls enclosing habitable or usablespace shall be dampproofed or waterproofed in accordancewith the applicable building code. Dampproofing and water-proofing materials for stay-in-place forms shall be compatiblewith the form material. In the absence of a code, concretefoundation walls enclosing habitable or usable space shall bedampproofed from the top of the footing to above finishedground level. In areas where a high water table or othersevere soil-water conditions are known to exist, exteriorconcrete foundation walls enclosing habitable or usablespace shall be waterproofed with a membrane extendingfrom the top of the footing to above finished ground level.Dampproofing and waterproofing materials shall be appliedin accordance with the manufacturer’s recommendations.
3.5 TERMITE PROTECTIONREQUIREMENTSStructures consisting of materials subject to termite attack(i.e., untreated wood) shall be protected against termiteinfestation in accordance with the applicable building code.
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Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
3-4
Table 3.1. Minimum Width of Concrete Footings for Concrete Walls1,2,3,4 (inches)
Max.number of
stories5
Max.roof span6
(ft)
Max.floorspan7
(ft)
Minimum load-bearing value of soil8 (psf)1500 2000 2500 3000 3500 4000
Ground snow load9 (psf)30 70 30 70 30 70 30 70 30 70 30 70
Group 1 – 4-inch flat, 6-inch waffle-grid, or 6-inch screen-grid wall thickness10
One story32
20 20 24 15 18 12 14 10 12 9 10 8 932 22 26 17 19 13 15 11 13 10 11 8 10
4020 22 26 16 19 13 16 11 13 9 11 8 1032 24 28 18 21 14 17 12 14 10 12 9 10
Two story32
20 27 30 20 23 16 18 14 15 12 13 10 1132 31 34 23 25 19 20 16 17 13 15 12 13
4020 29 33 21 25 17 20 14 16 12 14 11 1232 32 36 24 27 19 22 16 18 14 15 12 14
Group 2 – 6-inch flat or 8-in waffle-grid wall thickness10,11
One story32
20 22 25 16 19 13 15 11 12 9 11 8 932 23 27 18 20 14 16 12 13 10 11 9 10
4020 23 27 17 20 14 16 12 14 10 12 9 1032 25 29 19 22 15 17 12 15 11 12 9 11
Two story32
20 30 33 22 25 18 20 15 16 13 14 11 1232 33 36 25 27 20 22 17 18 14 16 13 14
4020 31 35 23 26 19 21 16 18 13 15 12 1332 35 39 26 29 21 23 17 19 15 17 13 14
Group 3 – 8-inch flat wall thickness10,12
One story32
20 25 28 19 21 15 17 12 14 11 12 9 1132 27 30 20 23 16 18 13 15 11 13 10 11
4020 26 30 20 23 16 18 13 15 11 13 10 1132 28 32 21 24 17 19 14 16 12 14 11 12
Two story32
20 34 38 26 28 21 23 17 19 15 16 13 1432 38 41 29 31 23 25 19 21 16 18 14 15
4020 36 40 27 30 21 24 18 20 15 17 13 1532 39 43 30 33 24 26 20 22 17 19 15 16
Group 4 – 10-inch flat wall thickness10
One story32
20 28 32 21 24 17 19 14 16 12 14 11 1232 30 33 23 25 18 20 15 17 13 14 11 13
4020 30 34 22 25 18 20 15 17 13 14 11 1332 32 36 24 27 19 21 16 18 14 15 12 13
Two story32
20 39 43 29 32 24 26 20 21 17 18 15 1632 43 46 32 35 26 28 22 23 19 20 16 17
4020 41 45 31 34 24 27 20 22 17 19 15 1732 44 48 33 36 27 29 22 24 19 21 17 18
Additional footing width for masonry veneer4,13,14
One story 5 3 3 2 2 2Two story 6 5 4 3 3 2
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3-5
Chapter 3 – Footings and Foundation Walls
For SI: 1 inch = 25.4 mm; 1 foot = 0.3048 m; 1 psf = 0.0479 kN/m2
1 Minimum footing thickness shall be the greater of: the projection of the footing beyond the face of the concrete wall, one-third of the footing width,6 inches (152 mm), and 11 inches (279 mm) where vertical wall reinforcement is required to extend into the footing in accordance with Section 6.2.
2 Footings shall have a width that allows for a nominal 2-inch (51-mm) projection from either face of the concrete in the wall to the edge of thefooting. Where masonry veneer is supported directly on the footing, the required projection shall be measured from the face of the veneer.
3 Tabulated footing widths are based on the weight of concrete walls as indicated in Table 2.1, plus an allowance of 2 psf (0.096 kN/m2) for interiorwall finish and 11 psf (0.527 kN/m2)for exterior wall finish. Where two or more wall types are grouped, the greatest weight of all those in the groupwas used.
4 Masonry veneer is not permitted for multiple dwellings assigned to Seismic Design Category C and all buildings assigned to Seismic Design CategoryD0, D1 or D2.
5 Basement walls shall not be considered as a story in determining footing widths, because table values assume the building has a basement. Wherethe building does not have a basement and the height of the foundation wall measured from the top of the footing to top of the first floor does notexceed 5 feet (1.5 m), footing widths are permitted to be reduced 10%. This reduction also applies to the additional footing width for masonryveneer.
6 For roof spans of less than 32 feet (9.8 m), use footing width for 32 feet (9.8 m) roof span. For roof spans between 32 (9.8) and 40 feet (12.2 m),use footing width for 40 feet (12.2 m) roof span, or determine footing width by interpolation.
7 For floor spans of less than 20 feet (6.1 m), use footing width for 20 feet (6.1 m) floor span. For floor spans between 20 (6.1) and 32 feet (9.8 m),use footing width for 32 feet (9.8 m) floor span, or determine footing width by interpolation.
8 To determined required footing width for soil bearing values of greater than 1,500 psf (71.85 kN/m2) that are not shown in the table, multiply thefooting width for 1,500 psf (71.85 kN/m2) soil by 1,500 (71.85 kN/m2) and divide by the load bearing value of the soil for which the footing width isdesired.
9 For ground snow loads between 30 (1.44 kN/m2) and 70 psf (3.35 kN/m2), use footings widths shown for 70 psf (3.35 kN/m2) or determine by inter-polation.
10 See Table 2.1 for tolerance from nominal thickness permitted for flat walls, and thicknesses and dimensions of waffle- and screen-grid walls.11 Tabulated footing widths based on use of a 6-inch (152 mm) nominal flat or 8-inch (203 mm) nominal waffle-grid foundation wall and above-grade
wall. Where an 8-inch (203 mm) or 10-inch (254 mm) nominal flat foundation wall is used with an above-grade 6-inch (152 mm) nominal flat or8-inch (203 mm) nominal waffle-grid wall, use footing width required for 8-inch (203 mm) or 10-inch (254 mm) nominal flat wall, or interpolatemidway between footing widths required for the foundation wall and above-grade wall.
12 Tabulated footing widths based on use of an 8-inch (203 mm) nominal flat foundation wall and above-grade wall. Where a 10-inch (254 mm) nominalflat foundation wall is used with an above-grade 8-inch (203 mm) nominal flat wall, use footing width required for a 10-inch (254 mm) nominal flatwall, or interpolate mid-way between footing widths required for the 10-inch (254 mm) nominal flat foundation wall and an 8-inch (203 mm) nominalflat above-grade wall.
13 Where masonry veneer is installed, the tabulated additional footing width is based on an installed weight of 40 psf (1.92 kN/m2) for the veneer, minus11 psf (0.527 kN/m2) to compensate for the exterior finish of 11 psf (0.527 kN/m2) which is already included. See Note 3.
14 It is assumed that the masonry veneer is supported directly on the footing.
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Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
3-6
Max.unsupported
wallheightin firststory(ft)
Heightof
stemwall3
(ft)
Max.designlateral
soilload
(psf/ft)
Required factored tributary weight of slab-on-ground per linear foot of stem wall, (plf)Basic wind speed (mph) and exposure category
85B 90B 100B 110B 120B 130B 140B 150B 166B 179B 192B– – 85C 90C 100C 110C 120C 130C 140C 150C 163C– – – 85D 90D 100D 110D 120D 130D 140D 150D
Design wind pressure, p (psf)14.73 16.52 20.42 24.67 29.36 34.46 40.70 47.88 56.19 65.17 74.81
8
230 186 200 230 263 299 339 388 443 508 578 65345 204 218 249 282 318 358 406 462 527 597 67260 223 237 267 300 337 377 425 481 546 615 690
430 307 324 360 398 441 488 545 611 687 769 85745 377 393 429 468 511 557 615 680 756 838 92760 446 463 498 537 580 627 684 750 826 908 996
630 493 512 553 598 647 701 766 842 930 1024 112545 645 664 705 750 799 853 919 994 1082 1176 127860 798 816 857 902 951 1005 1071 1146 1234 1328 1430
10
230 203 219 256 296 340 388 446 513 591 675 76645 221 238 275 314 358 406 465 532 610 694 78560 240 257 293 333 377 425 483 551 629 713 803
430 324 343 385 431 482 536 603 681 770 866 97045 394 413 455 501 551 606 673 750 839 936 104060 463 482 524 570 620 675 742 820 909 1005 1109
630 510 532 579 630 687 749 825 912 1013 1122 123845 662 684 731 783 840 901 977 1064 1165 1274 139160 814 836 883 935 992 1054 1129 1216 1317 1426 1543
For SI: 1 foot = 0.3048 m; 1 psf = 0.0479 kN/m2; 1 plf = 0.0146 kN/m; 1 mph = 0.4470 m/s 1 psf/ft = 0.1571 kN/m2/m1 For intermediate values of basic wind speed, unsupported wall height, and height of stem wall, use next higher value, or determine by interpolation.2 Values are based on first story wall being side-bearing (see Chapter 4). If construction supported by first-story wall is bearing on top of wall (top-
bearing), tabulated values are permitted to be reduced by 34 plf (0.496 kN/m) for 8-foot (2.4 m) high walls, and 27 plf (0.394 kN/m) for 10-foot(3.0 m) high walls. For top-bearing walls between 8 (2.4) and 10 feet (3.0 m) in height, the reduction shall be based on a wall height of 10 feet(3.0 m), or determined by interpolation.
3 Height of stem wall is the distance from the exterior finish ground level to the top of the slab-on-ground.
Table 3.2. Required Tributary Weight of Slab-on-Ground for Anchorage of Stem Wall1,2
Minimumthickness of slab-on-ground (in.)
Factored tributary weight provided by slab-on-ground per linear foot of stem wall, (plf)
Dimension of slab-on-ground perpendicular to stem wall, (ft)
10 15 20 25 30 35 40 50 60
3.5 275 413 551 689 827 965 1103 1378 1654
4 315 473 630 788 945 1103 1260 1575 1890
5 394 591 788 984 1181 1378 1575 1969 2363
6 473 709 945 1181 1418 1654 1890 2363 2835
8 630 945 1260 1575 1890 2205 2520 3150 3780
Table 3.3. Tributary Weight Provided by Slab-on-Ground for Anchorage of Stem Wall1
For SI: 1 inch = 25.4 mm; 1 foot = 0.3048 m; 1 plf = 0.0146 kN/m1 For intermediate values of slab thickness and dimension of slab perpendicular to wall, use the next lower value, or determine by interpolation.
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Chapter 3 – Footings and Foundation Walls
Table 3.4. Minimum Vertical Reinforcement for Concrete Crawlspace Walls1,2,3,4,5,6,7,10
Shape ofconcrete walls
Nominal wallthickness8 (in.)
Minimum vertical reinforcement – bar size No. and spacing (in.)Maximum design lateral soil load
30 psf/ft 45 psf/ft 60 psf/ft
Flat
49 4@48 4@38 4@34
6 NR NR NR
8 NR NR NR
10 NR NR NR
Waffle-grid6 4@48 4@48 4@48
8 NR NR NR
Screen-grid 6 4@48 4@48 4@48
For SI: 1 inch = 25.4 mm; 1 foot = 0.3048 m; 1 psf/ft = 0.1571 kN/m2/m1 Table values are based on reinforcing bars with a minimum yield strength of 60,000 psi (420 MPa), concrete with a minimum specified compressive
strength of 2,500 psi (17.2 MPa), and vertical reinforcement being located at the centerline of the wall. See Section 3.3.2 Vertical reinforcement with a yield strength of less than 60,000 psi (420 MPa) and/or bars of a different size than specified in the table are permitted
in accordance with Section 2.5.7 and Table 2.3.3 In lieu of using No. 4 bars, No. 3 bars are permitted provided the spacing shown in the table or determined in accordance with Note 2 is reduced by
50%.4 NR indicates no vertical wall reinforcement is required, except for 6-inch (152 mm) nominal flat walls formed with stay-in-place forming systems in
which case vertical reinforcement shall be No. 3@24 (610 mm) or No. 4@48 inches (1219 mm) on center.5 Applicable only to crawlspace walls 5 feet (1.5 m) or less in unsupported height with a maximum unbalanced backfill height of 4 feet (1.2 m).6 Interpolation shall not be permitted.7 Where walls will retain 4 feet (1.2 m) of unbalanced backfill, they shall be laterally supported at the top and bottom before backfilling.8 Nominal thicknesses are shown for walls. See Table 2.1 for tolerance from nominal thickness permitted for flat walls and thicknesses and dimensions
of waffle- and screen-grid walls.9 Applicable only to one-story construction with floor bearing on top of crawlspace wall.
10 See Sections 3.2.2, 3.2.4 and 3.2.5 for minimum reinforcement required for crawlspace walls supporting above-grade concrete walls.
Table 3.5. Minimum Horizontal Reinforcement for Concrete Basement Walls1,2
Maximum unsupported height ofbasement wall-feet (meters)
Location of horizontal reinforcement
≤ 8 (2.4) One No. 4 bar within 12 inches (305 mm) of the top of the wall story andone No. 4 bar near mid-height of the wall story
> 8 (2.4) One No. 4 bar within 12 inches (305 mm) of the top of the wall story andone No. 4 bar near third points in the wall story
1 Horizontal reinforcement requirements are for reinforcing bars with a minimum yield strength of 40,000 psi (280 MPa) and concrete with a minimumconcrete compressive strength 2,500 psi (17.2 MPa).
2 See Sections 3.2.3, 3.2.4 and 3.2.5 for minimum reinforcement required for basement walls supporting above-grade concrete walls.
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Table 3.6. Minimum Vertical Reinforcement for 6-Inch (152 mm) Nominal Flat Concrete Basement Walls1,2,3,4,5,7,8,9,10
Maximumunsupported wall
height (ft)
Maximumunbalanced
backfillheight6 (ft)
Minimum vertical reinforcement – bar size No. and spacing (in.)
Maximum design lateral soil load
30 psf/ft 45 psf/ft 60 psf/ft
8
4 NR NR NR
5 NR 5@39 6@48
6 5@39 6@48 6@35
7 6@48 6@34 6@25
8 6@39 6@25 6@18
9
4 NR NR NR
5 NR 5@37 6@48
6 5@36 6@44 6@32
7 6@47 6@30 6@22
8 6@34 6@22 6@16
9 6@27 6@17 DR
10
4 NR NR NR
5 NR 5@35 6@48
6 6@48 6@41 6@30
7 6@43 6@28 6@20
8 6@31 6@20 DR
9 6@24 6@15 DR
10 6@19 DR DR
For SI: 1 inch = 25.4 mm; 1 foot = 0.3048 m; 1 psf/ft = 0.1571 kN/m2/m1 Table values are based on reinforcing bars with a minimum yield strength of 60,000 psi (420 MPa), concrete with a minimum specified compressive
strength of 2,500 psi (17.2 MPa), and vertical reinforcement being located at the centerline of the wall. See Section 3.3. 2 Vertical reinforcement with a yield strength of less than 60,000 psi (420 MPa) and/or bars of a different size than specified in the table are permitted
in accordance with Section 2.5.7 and Table 2.3.3 Deflection criterion is L/240, where L is the height of the basement wall in inches.4 Interpolation shall not be permitted.5 Where walls will retain 4 feet (1.2 m) or greater of unbalanced backfill, they shall be laterally supported at the top and bottom before backfilling.6 Refer to Chapter 1 for the definition of unbalanced backfill height.7 NR indicates no vertical wall reinforcement is required, except for 6-inch (152 mm) nominal walls formed with stay-in-place forming systems in which
case vertical reinforcement shall be No. 4@48 inches (1219 mm) on center.8 See Sections 3.2.3, 3.2.4 and 3.2.5 for minimum reinforcement required for basement walls supporting above-grade concrete walls.9 See Table 2.1 for tolerance from nominal thickness permitted for flat walls.
10 DR means design is required in accordance with the applicable building code, or where there is no code in accordance with ACI 318.
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Chapter 3 – Footings and Foundation Walls
Table 3.7. Minimum Vertical Reinforcement for 8-Inch (203 mm) Nominal Flat Concrete Basement Walls1,2,3,4,5,6,8,9
For SI: 1 inch = 25.4 mm; 1 foot = 0.3048 m; 1 psf/ft = 0.1571 kN/m2/m1 Table values are based on reinforcing bars with a minimum yield strength of 60,000 psi (420 MPa), concrete with a minimum specified compressive
strength of 2,500 psi (17.2 MPa), and vertical reinforcement being located at the centerline of the wall. See Section 3.3.2 Vertical reinforcement with a yield strength of less than 60,000 psi (420 MPa) and/or bars of a different size than specified in the table are permitted
in accordance with Section 2.5.7 and Table 2.3.3 NR indicates no vertical reinforcement is required. 4 Deflection criterion is L/240, where L is the height of the basement wall in inches.5 Interpolation shall not be permitted.6 Where walls will retain 4 feet (1.2 m) or greater of unbalanced backfill, they shall be laterally supported at the top and bottom before backfilling.7 Refer to Chapter 1 for the definition of unbalanced backfill height.8 See Sections 3.2.3, 3.2.4 and 3.2.5 for minimum reinforcement required for basement walls supporting above-grade concrete walls.9 See Table 2.1 for tolerance from nominal thickness permitted for flat walls.
Maximumunsupported wall
height (ft)
Maximumunbalanced
backfillheight7 (ft)
Minimum vertical reinforcement – bar size No. and spacing (in.)
Maximum design lateral soil load
30 psf/ft 45 psf/ft 60 psf/ft
8
4 NR NR NR
5 NR NR NR
6 NR NR 6@37
7 NR 6@36 6@35
8 6@41 6@35 6@26
9
4 NR NR NR
5 NR NR NR
6 NR NR 6@35
7 NR 6@35 6@32
8 6@36 6@32 6@23
9 6@35 6@25 6@18
10
4 NR NR NR
5 NR NR NR
6 NR NR 6@35
7 NR 6@35 6@29
8 6@35 6@29 6@21
9 6@34 6@22 6@16
10 6@27 6@17 6@13
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Table 3.8. Minimum Vertical Reinforcement for 10-Inch (252 mm) Nominal Flat Concrete Basement Walls1,2,3,4,5,6,8,9
Maximumunsupported wall
height (ft)
Maximumunbalanced
backfillheight7 (ft)
Minimum vertical reinforcement – bar size No. and spacing (in.)
Maximum design lateral soil load
30 psf/ft 45 psf/ft 60 psf/ft
8
4 NR NR NR
5 NR NR NR
6 NR NR NR
7 NR NR NR
8 6@48 6@35 6@28
9
4 NR NR NR
5 NR NR NR
6 NR NR NR
7 NR NR 6@31
8 NR 6@31 6@28
9 6@37 6@28 6@24
10
4 NR NR NR
5 NR NR NR
6 NR NR NR
7 NR NR 6@28
8 NR 6@28 6@28
9 6@33 6@28 6@21
10 6@28 6@23 6@17
For SI: 1 inch = 25.4 mm; 1 foot = 0.3048 m; 1 psf/ft = 0.1571 kN/m2/m1 Table values are based on reinforcing bars with a minimum yield strength of 60,000 psi (420 MPa), concrete with a minimum specified compressive
strength of 2,500 psi (17.2 MPa), and vertical reinforcement being located at the centerline of the wall. See Section 3.3.2 Vertical reinforcement with a yield strength of less than 60,000 psi (420 MPa) and/or bars of a different size than specified in the table are permitted
in accordance with Section 2.5.7 and Table 2.3.3 NR indicates no vertical reinforcement is required. 4 Deflection criterion is L/240, where L is the height of the basement wall in inches.5 Interpolation shall not be permitted.6 Where walls will retain 4 feet (1.2 m) or greater of unbalanced backfill, they shall be laterally supported at the top and bottom before backfilling.7 Refer to Chapter 1 for the definition of unbalanced backfill height.8 See Sections 3.2.3, 3.2.4 and 3.2.5 for minimum reinforcement required for basement walls supporting above-grade concrete walls.9 See Table 2.1 for tolerance from nominal thickness permitted for flat walls.
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Chapter 3 – Footings and Foundation Walls
Table 3.9. Minimum Vertical Reinforcement for 6-Inch (152 mm) Waffle-Grid Basement Walls1,2,3,4,5,7,8,9
Maximumunsupported wall
height (ft)
Maximumunbalanced
backfillheight6 (ft)
Minimum vertical reinforcement – bar size No. and spacing (in.)
Maximum design lateral soil load
30 psf/ft 45 psf/ft 60 psf/ft
8
4 4@48 4@46 4@39
5 4@45 5@46 6@47
6 5@45 6@40 DR
7 6@44 DR DR
8 6@32 DR DR
9
4 4@48 4@46 4@37
5 4@42 5@43 6@44
6 5@41 6@37 DR
7 6@39 DR DR
≥ 8 . DR DR DR
10
4 4@48 4@46 4@35
5 4@40 5@40 6@41
6 5@38 6@34 DR
7 6@36 DR DR
≥ 8 . DR DR DR
For SI: 1 inch = 25.4 mm; 1 foot = 0.3048 m; 1 psf/ft = 0.1571 kN/m2/m1 Table values are based on reinforcing bars with a minimum yield strength of 60,000 psi (420 MPa), concrete with a minimum specified compressive
strength of 2,500 psi (17.2 MPa), and vertical reinforcement being located at the centerline of the wall. See Section 3.3.2 Vertical reinforcement with a yield strength of less than 60,000 psi (420 MPa) and/or bars of a different size than specified in the table are permitted
in accordance with Section 2.5.7 and Table 2.3.3 Deflection criterion is L/240, where L is the height of the basement wall in inches.4 Interpolation shall not be permitted.5 Where walls will retain 4 feet (1.2 m) or greater of unbalanced backfill, they shall be laterally supported at the top and bottom before backfilling.6 Refer to Chapter 1 for the definition of unbalanced backfill height.7 See Sections 3.2.3, 3.2.4 and 3.2.5 for minimum reinforcement required for basement walls supporting above-grade concrete walls.8 See Table 2.1 for thicknesses and dimensions of waffle-grid walls.9 DR means design is required in accordance with the applicable building code, or where there is no code in accordance with ACI 318.
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Table 3.10. Minimum Vertical Reinforcement for 8-Inch (203 mm) Waffle-Grid Basement Walls1,2,3,4,5,6,8,9,10
Maximumunsupported wall
height (ft)
Maximumunbalanced
backfillheight7 (ft)
Minimum vertical reinforcement – bar size No. and spacing (in.)
Maximum design lateral soil load
30 psf/ft 45 psf/ft 60 psf/ft
8
4 NR NR NR
5 NR 5@48 5@46
6 5@48 5@43 6@45
7 5@46 6@43 6@31
8 6@48 6@32 6@23
9
4 NR NR NR
5 NR 5@47 5@46
6 5@46 5@39 6@41
7 5@42 6@38 6@28
8 6@44 6@28 6@20
9 6@34 6@21 DR
10
4 NR NR NR
5 NR 5@46 5@44
6 5@46 5@37 6@38
7 5@38 6@35 6@25
8 6@39 6@25 DR
9 6@30 DR DR
10 6@24 DR DR
For SI: 1 inch = 25.4 mm; 1 foot = 0.3048 m; 1 psf/ft = 0.1571 kN/m2/m1 Table values are based on reinforcing bars with a minimum yield strength of 60,000 psi (420 MPa), concrete with a minimum specified compressive
strength of 2,500 psi (17.2 MPa), and vertical reinforcement being located at the centerline of the wall. See Section 3.3.2 Vertical reinforcement with a yield strength of less than 60,000 psi (420 MPa) and/or bars of a different size than specified in the table are permitted
in accordance with Section 2.5.7 and Table 2.3.3 NR indicates no vertical reinforcement is required. 4 Deflection criterion is L/240, where L is the height of the basement wall in inches.5 Interpolation shall not be permitted.6 Where walls will retain 4 feet (1.2 m) or greater of unbalanced backfill, they shall be laterally supported at the top and bottom before backfilling.7 Refer to Chapter 1 for the definition of unbalanced backfill height.8 See Sections 3.2.3, 3.2.4 and 3.2.5 for minimum reinforcement required for basement walls supporting above-grade concrete walls.9 See Table 2.1 for thicknesses and dimensions of waffle-grid walls.
10 DR means design is required in accordance with the applicable building code, or where there is no code in accordance with ACI 318.
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Chapter 3 – Footings and Foundation Walls
Table 3.11. Minimum Vertical Reinforcement for 6-Inch (152 mm) Screen-Grid Basement Walls1,2,3,4,5,7,8,9
Maximumunsupported wall
height (ft)
Maximumunbalanced
backfillheight6 (ft)
Minimum vertical reinforcement – bar size No. and spacing (in.)
Maximum design lateral soil load
30 psf/ft 45 psf/ft 60 psf/ft
8
4 4@48 4@48 4@43
5 4@48 5@48 5@37
6 5@48 6@45 6@32
7 6@48 DR DR
8 6@36 DR DR
9
4 4@48 4@48 4@41
5 4@48 5@48 6@48
6 5@45 6@41 DR
7 6@43 DR DR
≥ 8 . DR DR DR
10
4 4@48 4@48 4@39
5 4@44 5@44 6@46
6 5@42 6@38 DR
7 6@40 DR DR
≥ 8 . DR DR DR
For SI: 1 inch = 25.4 mm; 1 foot = 0.3048 m; 1 psf/ft = 0.1571 kN/m2/m1 Table values are based on reinforcing bars with a minimum yield strength of 60,000 psi (420 MPa), concrete with a minimum specified compressive
strength of 2,500 psi (17.2 MPa), and vertical reinforcement being located at the centerline of the wall. See Section 3.3.2 Vertical reinforcement with a yield strength of less than 60,000 psi (420 MPa) and/or bars of a different size than specified in the table are permitted
in accordance with Section 2.5.7 and Table 2.3.3 Deflection criterion is L/240, where L is the height of the basement wall in inches.4 Interpolation shall not be permitted.5 Where walls will retain 4 feet (1.2 m) or greater of unbalanced backfill, they shall be laterally supported at the top and bottom before backfilling.6 Refer to Chapter 1 for the definition of unbalanced backfill height.7 See Sections 3.2.3, 3.2.4 and 3.2.5 for minimum reinforcement required for basement walls supporting above-grade concrete walls.8 See Table 2.1 for thicknesses and dimensions of screen-grid walls.9 DR means design is required in accordance with the applicable building code, or where there is no code in accordance with ACI 318.
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Table 3.12. Minimum Vertical Reinforcement for 6-, 8-, 10- and 12-Inch Nominal Flat Basement Walls1,2,3,4,5,6,8,9,10,11,14
Maximumwall
height(ft)
Maximumunbalanced
backfillheight7 (ft)
Minimum vertical reinforcement – bar size No. and spacing (in.)
Maximum design lateral soil load
30 psf/ft 45 psf/ft 60 psf/ft
Minimum nominal wall thickness, (in.)
6 8 10 12 6 8 10 12 6 8 10 12
54 NR NR NR NR NR NR NR NR NR NR NR NR
5 NR NR NR NR NR NR NR NR NR NR NR NR
6
4 NR NR NR NR NR NR NR NR NR NR NR NR
5 NR NR NR NR NR NR12 NR NR 4@35 NR12 NR NR
6 NR NR NR NR 5@48 NR NR NR 5@36 NR NR NR
7
4 NR NR NR NR NR NR NR NR NR NR NR NR
5 NR NR NR NR NR NR NR NR 5@47 NR NR NR
6 NR NR NR NR 5@42 NR NR NR 6@43 5@48 NR12 NR
7 5@46 NR NR NR 6@42 5@46 NR12 NR 6@34 6@48 NR NR
8
4 NR NR NR NR NR NR NR NR NR NR NR NR
5 NR NR NR NR 4@38 NR12 NR NR 5@43 NR NR NR
6 4@37 NR12 NR NR 5@37 NR NR NR 6@37 5@43 NR12 NR
7 5@40 NR NR NR 6@37 5@41 NR12 NR 6@34 6@43 NR NR
8 6@43 5@47 NR12 NR 6@34 6@43 NR NR 6@27 6@32 6@44 NR
9
4 NR NR NR NR NR NR NR NR NR NR NR NR
5 NR NR NR NR 4@35 NR12 NR NR 5@40 NR NR NR
6 4@34 NR12 NR NR 6@48 NR NR NR 6@36 5@39 NR12 NR
7 5@36 NR NR NR 6@34 5@37 NR NR 6@33 6@38 5@37 NR12
8 6@38 5@41 NR12 NR 6@33 6@38 5@37 NR12 6@24 6@29 6@39 4@4813
9 6@34 6@46 NR NR 6@26 6@30 6@41 NR 6@19 6@23 6@30 6@39
10
4 NR NR NR NR NR NR NR NR NR NR NR NR
5 NR NR NR NR 4@33 NR12 NR NR 5@38 NR NR NR
6 5@48 NR12 NR NR 6@45 NR NR NR 6@34 5@37 NR NR
7 6@47 NR NR NR 6@34 6@48 NR NR 6@30 6@35 6@48 NR12
8 6@34 5@38 NR NR 6@30 6@34 6@47 NR12 6@22 6@26 6@35 6@4513
9 6@34 6@41 4@48 NR12 6@23 6@27 6@35 4@4813 DR 6@22 6@27 6@34
10 6@28 6@33 6@45 NR DR 6@23 6@29 6@38 DR 6@22 6@22 6@28
For SI: 1 inch = 25.4 mm; 1 foot = 0.3048 m; 1 psf/ft = 0.1571 kN/m2/m
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Chapter 3 – Footings and Foundation Walls
1 Table values are based on reinforcing bars with a minimum yield strength of 60,000 psi (420 MPa).2 Vertical reinforcement with a yield strength of less than 60,000 psi (420 MPa) and/or bars of a different size than specified in the table are permitted
in accordance with Section 2.5.7 and Table 2.3.3 NR indicates no vertical wall reinforcement is required, except for 6-inch (152 mm) nominal walls formed with stay-in-place forming systems in which
case vertical reinforcement shall be No. 4@48 inches (1219 mm) on center.4 Allowable deflection criterion is L/240, where L is the unsupported height of the basement wall in inches.5 Interpolation shall not be permitted.6 Where walls will retain 4 feet (1.2 m) or greater of unbalanced backfill, they shall be laterally supported at the top and bottom before backfilling.7 Refer to Chapter 1 for the definition of unbalanced backfill height.8 Vertical reinforcement shall be located to provide a cover of 1.25 inches (32 mm) measured from the inside face of the wall. The center of the steel
shall not vary from the specified location by more than the greater of 10% of the wall thickness and 3⁄8-inch (10 mm).9 Concrete cover for reinforcement measured from the inside face of the wall shall not be less than 3⁄4-inch (19 mm). Concrete cover for reinforcement
measured from the outside face of the wall shall not be less than 11⁄2 inches (38 mm) for No. 5 bars and smaller, and not less than 2 inches (51 mm)for larger bars.
10 DR means design is required in accordance with the applicable building code, or where there is no code in accordance with ACI 318.11 Concrete shall have a specified compressive strength, f 'c of not less than 2,500 psi (17.2 MPa) at 28 days, unless a higher strength is required by
Note 12 or 13.12 The minimum thickness is permitted to be reduced 2 inches (51 mm), provided the minimum specified compressive strength of concrete, f 'c, is 4,000
psi (27.6 MPa).13 A plain concrete wall with a minimum nominal thickness of 12 inches (305 mm) is permitted, provided the minimum specified compressive strength of
concrete, f c , is 3,500 psi (24.1 MPa).14 See Table 2.1 for tolerance from nominal thickness permitted for flat walls.
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Wall – stay-in-placeor removable form
Slab-on-ground
4 ft (1.2 m)maximum
Horizontal wallreinforcement as required
Vertical wallreinforcement as required
See Section 6.2
Footing asrequired
Section cut through flat wall or vertical core of a waffle- or screen-grid wall
2" Min. cover
6" (152 mm)Nominal min.
10" Min. (254 mm)height with webmaterial removed
Welded wirereinforcementSee Section 3.2.1.2for size designationand alternate barsize and spacing
No. 4 anchor barwith standard hook.See Section 3.2.1.2for spacing
Min. No. 4continuous
5"(127 mm)
5"(127 mm)
Tension development length – See Table 2.2
a. Stem wall not anchored to slab-on-ground
b. Stem wall anchored to slab-on-groundFigure 3.1. Concrete stem wall with slab-on-ground construction.
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Chapter 3 – Footings and Foundation Walls
Wall –stay-in-placeor removable form
Wall – stay-in-placeor removable form
Light-framed floor
Depth ofunbalancedfill, 4 ft (1.2 m)maximum
Horizontal wallreinforcementas required
Vertical wallreinforcementas requiredSee Section 6.2
Wall height, 5 ft(1.5 m) maximum
See Section 6.4
(b) Supporting Concrete Wall
(a) Supporting Light-Framed Wall
Light-framed floor
Light-framed wall system
Depth ofunbalancedfill, 4 ft (1.2 m)maximum
Horizontal wallreinforcementas required
Vertical wallreinforcementas required
See Section 6.2
Section cut through flat wall or vertical core of a waffle- or screen-grid wall
Section cut through flat wall or vertical core of a waffle- or screen-grid wall
See Section 6.4
Wall height, 5 ft(1.5 m) maximum
Wall – stay-in-placeor removable form
Figure 3.2. Concrete crawlspace wall construction.
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Depth ofunbalancedfill
Horizontal wallreinforcementas required
Wall –stay-in-place orremovable form
Vertical wallreinforcementas required
Section cut through flat wall or vertical core of a waffle- or screen-grid wall
See Section 6.4
Light-framed wallsystem
Light-framedfloor
SeeSection 6.2
Slab-on-ground
Depth ofunbalancedfill
Horizontal wallreinforcementas required
Wall –stay-in-place orremovable form
Vertical wallreinforcementas required
Section cut through flat wall or vertical core of a waffle- or screen-grid wall
See Section 6.4Light-framedfloor
SeeSection 6.2
Unsupported wallheight, 10 ft (3 m)maximum
Unsupported wallheight, 10 ft (3 m)maximum
Slab-on-ground
Wall
(a) Supporting Light-Framed Wall
(b) Supporting Concrete Wall
Figure 3.3. Concrete basement wall construction.
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Chapter 4Above-Grade Walls
4.1 ABOVE-GRADE WALLREQUIREMENTS
4.1.1 GeneralThe minimum thickness of loadbearing and non-loadbearingabove-grade walls and reinforcement shall be as set forth inthe appropriate table in this chapter based on the type ofwall form to be used. For multiple dwellings assigned toSeismic Design Category C and all buildings assigned toSeismic Design Category D0, D1 or D2, the minimum nominalthickness of above-grade walls shall be 6 inches (152 mm).The wall shall be designed in accordance with the applicablebuilding code, or where there is no code in accordance withACI 318 where: the wall or building is not within the limita-tions of Section 1.2 and Table 1.1, design is required by thetables in this chapter, or the wall is not within the scope ofthe tables in this chapter.
Above-grade concrete walls shall be constructed in accor -dance with this chapter and Figure 4.1, 4.2, 4.3, or 4.4.Above-grade concrete walls that are continuous with stemwalls and not laterally supported by the slab-on-groundshall be designed and constructed in accordance with thischapter and Figure 3.1. Concrete walls shall be supported oncontinuous foundation walls or slabs-on-ground that aremono lithic with the footing in accordance with Section 3.2.The min imum length of solid wall without openings shall bein accordance with Chapter 5. Reinforcement around open-ings, including lintels, shall be in accordance with Chapter 7.Lateral support for above-grade walls in the out-of-planedirection shall be provided by the roof system and floorframing system, if applicable, in accordance with Chapter 6.The wall thickness shall be equal to or greater than the thick-ness of the wall in the story above.
4.1.2 Wall Reinforcement for WindVertical wall reinforcement shall be determined from Table4.1, 4.2, 4.3 or 4.4, Section 4.1.3 and Section 5.2.2.2. Thereshall be a vertical bar at all corners of exterior walls. Unlessmore reinforcement is required by Section 4.1.3 or 5.2.2.1,the minimum horizontal reinforcement shall be four No. 4bars (Grade 40 (280 MPa)) placed as follows: top bar within12 inches (305 mm) of the top of the wall, bottom barwithin 12 inches (305 mm) of the finish floor, and one bareach at approximately one-third and two-thirds of the wallheight.
4.1.3 Wall Reinforcement for Seismic DesignCategories C, D0, D1 and D2
For multiple dwellings assigned to Seismic Design CategoryC, the minimum vertical and horizontal reinforcement shallbe one No. 5 bar (Grade 40 (280 MPa)) at 24 inches (610 m)on center or one No. 4 bar (Grade 40 (280 MPa)) at 16inches (407 mm) on center, but in no case shall the spacingof reinforcement exceed 24 inches (610 mm) on center. Forall buildings assigned to Seismic Design Category D0, D1 orD2, the minimum vertical and horizontal reinforcement shallbe one No. 5 bar (Grade 60 (420 MPa)) at 18 inches (457mm) on center or one No. 4 bar (Grade 60 (420 MPa)) at 12inches (305 mm) on center, but in no case shall the spacingof reinforcement exceed 18 inches (457 mm) on center. SeeSections 2.3.1, 5.2.2.1 and 5.2.2.2.
4.1.4 Concrete Strength for Seismic DesignCategories D0, D1 and D2
For all buildings assigned to Seismic Design Category D0, D1
or D2, the minimum specified compressive strength ofconcrete shall be 3,000 psi (20.7 MPa).
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4.1.5 Continuity of Wall ReinforcementBetween StoriesVertical reinforcement shall be continuous from the bottomof the foundation wall to the roof. Lap splices, whererequired, shall comply with Section 2.5.3 and Figure 2.4.Where splices are needed to provide the required continuity,dowel bars with a size and spacing to match the verticalabove-grade concrete wall reinforcement shall be embeddedin the foundation wall the distance required to develop thedowel bar in tension in accordance with Section 2.5.4 andFigure 2.5 and lap-spliced with the above-grade wall rein -forcement in accordance with Section 2.5.3 and Figure 2.4.
4.1.6 Termination of ReinforcementWhere indicated in items 1 through 4 below, vertical wallreinforcement in the top-most story with concrete walls shallbe terminated with a 90-degree standard hook complyingwith Section 2.5.5 and Figure 2.6.
1. In load bearing walls or portions thereof supporting roofframing members where the factored roof uplift force inaccordance with Table 7.1A is greater than 1,000 plf(14.60 kN/m)
2. Vertical bars adjacent to door and window openingsrequired by Section 7.1.2.
3. Vertical bars at the ends of required solid wall segments.See Section 5.2.2.2.
4. Intermediate vertical bars (other than end bars – see item3) in required solid wall segments where the adjustmentfactor, F, is based on the wall having horizontal shearreinforcement. See Section 5.2.2.2.
The bar extension of the hook shall be oriented parallel tothe horizontal wall reinforcement and be within 4 inches(102 mm) of the top of the wall.
Horizontal reinforcement shall be continuous around thebuilding corners by bending one of the bars and lap-splicingit with the bar in the other wall in accordance with Section2.5.3 and Figure 2.4.
Exception: In lieu of bending horizontal reinforcementat corners, separate bent reinforcing bars shall bepermitted provided that the bent bar is lap-spliced withthe horizontal reinforcement in both walls in accordancewith Section 2.5.3 and Figure 2.4.
Where indicated in items 1 and 2 below, horizontal wall reinforcement shall be terminated with a standard hookcomplying with Section 2.5.5 and Figure 2.6 or in a lap-splice, except at corners where the reinforcement shall becontinuous as required above.
1. In all buildings assigned to Seismic Design Category Aor B, and in detached one- and two-family dwellingsassigned to Seismic Design Category C in required solidwall segments where the adjustment factor, F, is basedon the wall having horizontal shear reinforcement. SeeSection 5.2.2.1.
2. In multiple dwellings assigned to Seismic DesignCategory C and for all buildings assigned to SeismicDesign Category D0, D1 or D2.
4.1.7 Location of Reinforcement in WallExcept for vertical reinforcement at the ends of required solidwall segments which shall be located as required by Section5.2.2.2, the location of the vertical reinforcement shall notvary from the center of the wall by more than the greater of10% of the wall thickness and 3⁄8-inch (10 mm). Horizontaland vertical reinforcement shall be located to provide notless than the minimum cover required by Section 2.5.1.
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Chapter 4 – Above-Grade Walls
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Table 4.1. Minimum Vertical Reinforcement for Flat Above-Grade Walls1,2,3,4,5,11
Basic wind speed(mph)
Maximumunsupportedwall height
per story (ft)
Minimum vertical reinforcement – bar size No. and spacing (in.)6,7,8
Nominal9 wall thickness (in.)
Exposure category 4 6 8 10
B C D Top10 Side10 Top10 Side10 Top10 Side10 Top10 Side10
85
8 4@48 4@48 4@48 4@48 4@48 4@48 4@48 4@48
9 4@48 4@43 4@48 4@48 4@48 4@48 4@48 4@48
10 4@47 4@36 4@48 4@48 4@48 4@48 4@48 4@48
90
8 4@48 4@47 4@48 4@48 4@48 4@48 4@48 4@48
9 4@48 4@39 4@48 4@48 4@48 4@48 4@48 4@48
10 4@42 4@34 4@48 4@48 4@48 4@48 4@48 4@48
100 85
8 4@48 4@40 4@48 4@48 4@48 4@48 4@48 4@48
9 4@42 4@34 4@48 4@48 4@48 4@48 4@48 4@48
10 4@34 4@34 4@48 4@48 4@48 4@48 4@48 4@48
110 90 85
8 4@44 4@34 4@48 4@48 4@48 4@48 4@48 4@48
9 4@34 4@34 4@48 4@48 4@48 4@48 4@48 4@48
10 4@34 4@31 4@48 4@37 4@48 4@48 4@48 4@48
120 100 90
8 4@36 4@34 4@48 4@48 4@48 4@48 4@48 4@48
9 4@34 4@32 4@48 4@38 4@48 4@48 4@48 4@48
10 4@30 4@27 4@48 5@48 4@48 4@48 4@48 4@48
130 110 100
8 4@34 4@34 4@48 4@48 4@48 4@48 4@48 4@48
9 4@32 4@28 4@48 4@33 4@48 4@48 4@48 4@48
10 4@26 4@23 4@48 5@43 4@48 4@48 4@48 4@48
140 120 110
8 4@34 4@30 4@48 4@35 4@48 4@48 4@48 4@48
9 4@27 4@24 4@48 5@44 4@48 4@48 4@48 4@48
10 4@21 4@19 5@41 5@37 4@48 4@48 4@48 4@48
150 130 120
8 4@29 4@26 4@48 5@47 4@48 4@48 4@48 4@48
9 4@23 4@20 5@43 5@38 4@48 4@48 4@48 4@48
10 4@18 4@16 5@35 5@34 4@48 4@48 4@48 4@48
166 140 130
8 4@25 4@22 5@47 5@41 4@48 4@48 4@48 4@48
9 4@19 4@17 5@37 5@34 4@48 4@48 4@48 4@48
10 4@15 4@14 5@34 5@34 4@48 5@37 4@48 4@48
179 150 140
8 4@21 4@19 5@40 5@36 4@48 4@48 4@48 4@48
9 4@16 4@15 5@34 5@34 4@48 5@39 4@48 4@48
10 DR DR 5@34 5@31 5@35 6@46 4@48 4@48
192 163 150
8 4@18 4@16 5@35 5@34 4@48 5@43 4@48 4@48
9 4@14 4@13 5@34 5@34 4@48 6@48 4@48 4@48
10 DR DR 5@29 5@27 6@43 6@40 4@48 4@48
For SI: 1 inch = 25.4 mm; 1 foot = 0.3048 m; 1 mph = 0.4470 m/s
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Chapter 4 – Above-Grade Walls
Notes for Tables 4.1 through 4.3.1 Table is based on ASCE 7 components and cladding wind pressures for an enclosed building using a mean roof height of 35 ft (10.7 m), interior wall
area 4, an effective wind area of 10 ft2 (0.9 m2), and topographic factor, Kzt, and importance factor, I, equal to 1.0.2 Table is based on concrete with a minimum specified compressive strength of 2,500 psi (17.2 MPa). See Section 4.1.4 for minimum strength of
concrete for buildings assigned to Seismic Design Category D0, D1 or D2.3 See Section 4.1.7 for location of reinforcement in wall.4 Deflection criterion is L/240, where L is the unsupported height of the wall in inches.5 Interpolation shall not be permitted.6 See Section 4.1.3 for minimum grade, and size and spacing of vertical wall reinforcement for multiple dwellings assigned to Seismic Design Category
C, and all buildings assigned to Seismic Design Category D0, D1 or D2. The more stringent provisions of that section or this table shall apply.7 Where No. 4 reinforcing bars at a spacing of 48 inches (1219 mm) are specified in the table, bars with a minimum yield strength of 40,000 psi (280
MPa) or 60,000 psi (420 MPa) are permitted to be used.8 Other than for No. 4 bars spaced at 48 inches (1219 mm) on center, table values are based on reinforcing bars with a minimum yield strength of
60,000 psi (420 MPa). Vertical reinforcement with a yield strength of less than 60,000 psi (420 MPa) and/or bars of a different size than specified inthe table are permitted in accordance with Section 2.5.7 and Table 2.3.
9 See Table 2.1 for tolerances on nominal thicknesses for flat walls, and minimum core dimensions and maximum spacing of horizontal and verticalcores for waffle- and screen-grid walls.
10 Top means gravity load from roof and/or floor construction bears on top of wall. Side means gravity load from floor construction is transferred to wallfrom a wood ledger or cold-formed steel track bolted to side of wall. Where floor framing members span parallel to the wall, the top bearing condi-tion is permitted to be used.
11 DR indicates design required.
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Table 4.2. Minimum Vertical Reinforcement for Waffle-Grid Above-Grade Walls1,2,3,4,5
Basic wind speed(mph)
Maximumunsupportedwall height
per story (ft)
Minimum vertical reinforcement – bar size No. and spacing (in.)6,7,8
Nominal9 wall thickness (in.)
Exposure category 6 8
B C D Top10 Side10 Top10 Side10
85
8 4@48 4@36, 5@48 4@48 4@48
9 4@48 4@30, 5@47 4@48 4@45
10 4@48 4@26, 5@40 4@48 4@39
90
8 4@48 4@33, 5@48 4@48 4@48
9 4@48 4@28, 5@43 4@48 4@42
10 4@31, 5@48 4@24, 5@37 4@48 4@36
100 85
8 4@48 4@28, 5@44 4@48 4@43
9 4@31, 5@48 4@24, 5@37 4@48 4@36
10 4@25, 5@39 4@24, 5@37 4@48 4@31, 5@48
110 90 85
8 4@33, 5@48 4@25, 5@38 4@48 4@38
9 4@26, 5@40 4@24, 5@37 4@48 4@31, 5@48
10 4@24, 5@37 4@23, 5@35 4@48 4@27, 5@41
120 100 90
8 4@27, 5@42 4@24, 5@37 4@48 4@33, 5@48
9 4@24, 5@37 4@23, 5@36 4@48 4@27, 5@43
10 4@23, 5@35 4@19, 5@30 4@48 4@23, 5@36
130 110 100
8 4@24, 5@37 4@24, 5@37 4@48 4@29, 5@45
9 4@24, 5@37 4@20, 5@32 4@48 4@24, 5@37
10 4@19, 5@30 4@17, 5@26 4@23, 5@36 4@20, 5@31
140 120 110
8 4@24, 5@37 4@22, 5@34 4@48 4@25, 5@39
9 4@20, 5@31 4@17, 5@27 4@24, 5@38 4@21, 5@32
10 4@16, 5@25 4@14, 5@22 4@20, 5@31 4@17, 5@27
150 130 120
8 4@22, 5@34 4@19, 5@29 4@26, 5@41 4@22, 5@34
9 4@17, 5@26 4@15, 5@23 4@21, 5@32 4@18, 5@28
10 4@13, 5@21 4@12, 5@19 4@17, 5@27 4@17, 5@27
166 140 130
8 4@18, 5@28 4@16, 5@25 4@22, 5@35 4@19, 5@30
9 4@14, 5@22 4@13, 5@20 4@18, 5@27 4@17, 5@27
10 5@17 5@16, 6@23 4@17, 5@27 4@17, 5@26
179 150 140
8 4@16, 5@24 4@14, 5@22 4@19, 5@30 4@17, 5@27
9 4@12, 5@19 4@11, 5@17 4@17, 5@27 4@17, 5@27
10 5@15 5@14, 6@19 4@16, 5@25 4@15, 5@23
192 163 150
8 4@13, 5@21 4@12, 5@19 4@17, 5@27 4@17, 5@27
9 5@16 5@15, 6@21 4@17, 5@27 4@16, 5@25
10 5@13 5@12, 6@17 4@14, 5@22 4@13, 5@20
For SI: 1 inch = 25.4 mm; 1 foot = 0.3048 m; 1 mph = 0.4470 m/sSee page 4-5 for notes to table.
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Chapter 4 – Above-Grade Walls
Table 4.3. Minimum Vertical Reinforcement for 6-inch Screen-Grid Above-Grade Walls1,2,3,4,5
Basic wind speed (mph) Maximumunsupportedwall height
per story (ft)
Minimum vertical reinforcement – bar size No. and spacing (in.)6,7,8
Nominal9 wall thickness (in.)Exposure category 6
B C D Top10 Side10
858 4@48 4@34, 5@489 4@48 4@29, 5@45
10 4@48 4@25, 5@39
908 4@48 4@31, 5@489 4@48 4@27, 5@41
10 4@30, 5@47 4@23, 5@35
100 858 4@48 4@27, 5@429 4@30, 5@47 4@23, 5@35
10 4@24, 5@38 4@22, 5@34
110 90 858 4@48 4@24, 5@379 4@25, 5@38 4@22, 5@34
10 4@22, 5@34 4@22, 5@34
120 100 908 4@26, 5@41 4@22, 5@349 4@22, 5@34 4@22, 5@34
10 4@22, 6@34 4@19, 5@26
130 110 1008 4@22, 5@35 4@22, 5@349 4@22, 5@34 4@20, 5@30
10 4@19, 5@29 4@16, 5@25
140 120 1108 4@22, 5@34 4@21, 5@329 4@20, 5@30 4@17, 5@26
10 4@16, 5@24 4@14, 5@21
150 130 1208 4@21, 5@33 4@18, 5@289 4@16, 5@26 4@14, 5@22
10 4@13, 5@20 4@12, 5@18
166 140 1308 4@18, 5@28 4@16, 5@249 4@14, 5@21 4@12, 5@19
10 5@17, 6@24 5@16, 6@22
179 150 1408 4@15, 5@24 4@14, 5@219 4@12, 5@18 5@17, 6@23
10 5@14, 6@20 5@13, 6@19
192 163 1508 4@13, 5@20 4@12, 5@189 5@16, 6@22 5@14, 6@20
10 5@12, 6@17 5@11, 6@16
For SI: 1 inch = 25.4 mm; 1 foot = 0.3048 m; 1 mph = 0.4470 m/sSee page 4-5 for notes to table.
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Table 4.4. Minimum Vertical Reinforcement for Flat, Waffle- and Screen-Grid Stem Walls Designed Continuous With Above-GradeWalls1,2,3,4,5,19,20
Basic wind speed(mph)
Height of stemwall,9,10
(ft)
Max. design
lateral soilload
(psf/ft)
Max.unsupported
height ofabove-grade
wall (ft)
Min. vertical reinforcement – bar size No. and spacing (in.)6,7,8
Wall type and nominal thickness, (in.)18
Exposure category Flat Waffle Screen
B C D 4 6 8 10 6 8 6
90
330
8 4@30 4@36 4@48 4@48 4@22 4@26 4@21
10 4@24 5@44 4@38 4@48 4@1715 4@21 4@1715
60 10 4@20 5@37 5@48 4@41 4@1516 4@18 4@1416
630 10 DR 5@2111 6@3512 6@41 DR 4@1017 DR
60 10 DR DR 6@2613 6@2814 DR DR DR
110 90 85
330
8 4@22 5@42 4@37 4@46 4@16 4@20 4@16
10 4@17 5@34 5@44 4@35 4@1215 4@17 4@1215
60 10 4@15 5@34 5@39 5@48 4@1116 4@17 4@1116
630 10 DR 5@1811 6@3512 6@35 DR 4@917 DR
60 10 DR DR 6@2313 6@2814 DR DR DR
120 100 90
330
8 4@19 5@37 5@48 4@40 4@14 4@17 4@14
10 4@14 5@34 5@38 5@48 4@1115 4@17 4@1015
60 10 4@13 5@33 6@48 5@43 4@1016 4@16 4@916
630 10 DR 5@1611 6@3312 6@32 DR 4@817 DR
60 10 DR DR 6@2213 6@2814 DR DR DR
140 120 110
330
8 4@14 5@34 5@38 5@48 4@11 4@17 4@10
10 DR 5@28 6@41 5@36 DR 4@13 DR
60 10 DR 5@29 6@43 5@38 DR 4@12 DR
630 10 DR 5@13 6@2712 6@28 DR DR DR
60 10 DR DR 6@1913 6@2514 DR DR DR
166 140 130
330
8 DR 5@28 6@41 5@37 DR 4@13 DR
10 DR 5@20 6@35 6@39 DR 4@10 DR
60 10 DR 5@19 6@35 6@37 DR 4@9 DR
630 10 DR DR 6@21 6@28 DR DR DR
60 10 DR DR 6@16 6@2114 DR DR DR
179 150 140
330
8 DR 5@24 6@36 6@46 DR 4@12 DR
10 DR 5@18 6@35 6@34 DR 4@8 DR
60 10 DR 5@17 6@34 6@32 DR 4@8 DR
630 10 DR DR 6@19 6@25 DR DR DR
60 10 DR DR 6@15 6@20 DR DR DR
192 163 150
330
8 DR 5@21 6@35 6@41 DR 4@10 DR
10 DR 5@15 6@31 6@30 DR 4@7 DR
60 10 DR 5@15 6@30 6@29 DR DR DR
630 10 DR DR 6@17 6@22 DR DR DR
60 10 DR DR 6@14 6@18 DR DR DR
For SI: 1 inch = 25.4 mm; 1 foot = 0.3048 m; 1 mph = 0.4470 m/s; 1 psf/ft = 0.1571 kN/m2/m
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1 Table is based on ASCE 7 components and cladding wind pressures for an enclosed building using a mean roof height of 35 ft (10.7 m), interior wallarea 4, an effective wind area of 10 ft2 (0.9 m2), and topographic factor, Kzt , and importance factor, I, equal to 1.0.
2 Table is based on concrete with a minimum specified compressive strength of 2,500 psi (17.2 MPa). See Section 4.1.4 for minimum strength ofconcrete for buildings assigned to Seismic Design Category D0, D1 or D2.
3 See Section 4.1.7 for location of reinforcement in wall.4 Deflection criterion is L/240, where L is the height of the wall in inches from the exterior finish ground level to the top of the above-grade wall.5 Interpolation shall not be permitted. For intermediate values of basic wind speed, heights of stem wall and above-grade wall, and design lateral soil
load, use next higher value.6 See Section 4.1.3 for minimum grade, and size and spacing of vertical wall reinforcement for multiple dwellings assigned to Seismic Design Category
C, and all buildings assigned to Seismic Design Category D0, D1 or D2. The more stringent provisions of that section or this table shall apply.7 Where No. 4 reinforcing bars at a spacing of 48 inches (1219 mm) are specified in the table, bars with a minimum yield strength of 40,000 psi (280
MPa) or 60,000 psi (420 MPa) are permitted to be used.8 Other than for No. 4 bars spaced at 48 inches (1219 mm) on center, table values are based on reinforcing bars with a minimum yield strength of
60,000 psi (420 MPa). Vertical reinforcement with a yield strength of less than 60,000 psi (420 MPa) and/or bars of a different size than specified inthe table are permitted in accordance with Section 2.5.7 and Table 2.3.
9 Height of stem wall is the distance from the exterior finish ground level to the top of the slab-on-ground.10 Where the distance from the exterior finish ground level to the top of the slab-on-ground is equal to or greater than 4 feet, the stem wall shall be
laterally supported at the top and bottom before backfilling. Where the wall is designed and constructed to be continuous with the above-grade wall,temporary supports bracing the top of the stem wall shall remain in place until the above-grade wall is laterally supported at the top by floor or roofconstruction.
11 In SDC D2 not less than No. [email protected] In SDC D2 not less than No. [email protected] In SDC D2 not less than No. 6@17, in SDC D1 not less than No. 6@18, in SDC D0, not less than No. 6@20, and in SDC C not less than No. [email protected] In SDC D2 not less than No. 6@19, in SDC D1 not less than No. 6@21, and in SDC D0 not less than No. [email protected] In SDC D2 not less than No. [email protected] In SDC D2 not less than No. [email protected] In SDC D2 not less than No. [email protected] See Table 2.1 for tolerances on nominal thicknesses, and minimum core dimensions and maximum spacing of horizontal and vertical cores for waffle-
and screen-grid walls.19 Tabulated values are applicable to construction where gravity loads bear on top of wall, and conditions where gravity loads from floor construction are
transferred to wall from a wood ledger or cold-formed steel track bolted to side of wall. See Tables 4.1, 4.2 and 4.3.20 DR indicates design required.
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Light-framed roof
Horizontal wallreinforcementas required
Vertical wallreinforcementas required
Section cut through flat wall or vertical core of a waffle- or screen-grid wall
Basement, crawlspace,or stem wall. For slab-on-ground footing see Figure 4.4
See Section 6.4
See Section6.5
Light-framed floor(or concreteslab-on-ground)
Wall – stay-in-placeor removable form
First-storyunsupportedwall height10 ft (3 m)maximum
Figure 4.1. Concrete wall supporting roof.
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Chapter 4 – Above-Grade Walls
Light-framed roof
Horizontal wallreinforcementas required
Vertical wallreinforcementas required
Section cut through flat wall or vertical core of a waffle- or screen-grid wall
Basement, crawlspace,or stem wall. For slab-on-ground footing see Figure 4.4
See Section 6.4
See Section6.4
Light-framed floor(or concreteslab-on-ground)
Light-framed wallsystem
Light-framed floor
Wall – stay-in-placeor removable form
First-storyunsupportedwall height10 ft (3 m)maximum
Second-storyunsupportedwall height10 ft (3 m)maximum
Figure 4.2. Concrete wall supporting light-framed second story wall and roof.
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Light-framed roof
Vertical wallreinforcementas required
Section cut through flat wall or vertical core of a waffle- or screen-grid wall
Basement, crawlspace,or stem wall. For slab-on-ground footing see Figure 4.4
See Section6.4
See Section 6.4
Light-framed floor(or concreteslab-on-ground)
Light-framed floor
Wall – stay-in-placeor removable form
First-storyunsupportedwall height10 ft (3 m)maximum
Second-storyunsupportedwall height10 ft (3 m)maximum
Horizontal wallreinforcementas required
See Section6.5
Figure 4.3. Concrete wall supporting concrete second story wall and roof.
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Chapter 4 – Above-Grade Walls
Wall – stay-in-placeor removable form
Monolithic concreteslab-on-ground and footing
Horizontal wallreinforcement as required
Vertical wallreinforcement as required
See Section 6.2
Insulation as required bygeneral building code
Section cut through flat wall or vertical core of a waffle- or screen-grid wall
No. 4 bar top and bottom inSeismic Design CategoryD0, D1, or D2 per Section 3.1.3.Locate bars as close to top andbottom as cover requirementswill permit.
12 in. (305 mm)minimum
Figure 4.4. Monolithic slab-on-ground supporting concrete wall.
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Chapter 5Solid Walls for Resistance to Lateral Forces
5.1 LENGTH OF SOLID WALLEach exterior wall line in each story shall have a total lengthof solid wall required by Sections 5.1.1 and 5.1.2. A solidwall is a section of flat, waffle-grid or screen-grid wall,extending the full story height without openings or penetra-tions, except those permitted by Section 5.2. Solid wallsegments that contribute to the total length of solid wallshall comply with Section 5.2.
5.1.1 Length of Solid Wall for WindAll buildings shall have solid walls in each exterior endwallline and sidewall line to resist lateral wind forces. The site-appropriate basic wind speed and exposure category shall beused to determine the unadjusted required total length ofsolid wall in each exterior endwall line and sidewall line fromTables 5.1A, B and C. For buildings with a mean roof heightof less than 35 feet (10.7 m), the unadjusted valuesdetermined from Tables 5.1A, B and C are permitted to bereduced by multiplying by the applicable factor from Table5.2; however, this reduction shall not apply to the minimumvalues in Tables 5.1A, B and C. Where the floor-to-ceilingheight of a story is less than 10 feet (3.1 m), the unadjustedvalues determined from Tables 5.1A, B and C, includingminimum values, are permitted to be reduced by multiplyingby the applicable factor from Table 5.3.
The unadjusted tabulated solid wall lengths in Tables 5.1A, Band C are based on a design strength of 840 pounds perfoot (12.26 kN/m) of length of solid wall segment. To accountfor solid wall segments having a different design strength,the actual length of an individual solid wall seg ment comply -ing with Section 5.2 that makes up a part of a solid wallshall be adjusted based the amount of vertical reinforcementat its ends and other attributes. Adjustment factor, F, for indi-vidual solid wall segments shall be deter mined from Table5.4A or B. In each exterior wall line in each story, the
adjusted lengths of solid wall segments being considered(i.e., the product of the adjustment factor and the length ofthe segment) shall satisfy Eq. 5-1.
F1A + F2B + … + Fn Z ≥ R5.2R5.3TL Eq. 5-1
Where A, B, … Z = actual length of individual solid wallsegments being considered in the exterior wall line beingevaluated (see Figure 5.2).
F1, F2 and Fn = adjustment factor applicable to solid wallsegment being considered from Table 5.4A or B
R5.2 = 1.0 or reduction factor for mean roof height fromTable 5.2
R5.3 = 1.0 or reduction factor for floor-to-ceiling wallheight from Table 5.3
TL = Unadjusted length of solid wall from Table 5.1A, B orC
Where the actual length of a solid wall segment is betweentwo lengths shown in Table 5.4A or B, or is greater than 48inches (1.2 m), use adjustment factor, F, for the next shortersegment length. No credit shall be taken for segments with alength less than required by Section 5.2.1.
The total length of solid wall after applying all reductionsand adjustments shall not be less than the greater of theminimum value and the length provided by two segmentscomplying with the minimum length requirements of Section5.2.1.
To facilitate compliance with Eq. 5-1, determine a requiredaverage adjustment factor, Fa, from Eq. 5-2.
R5.2R5.3TLFa = ------------------------------- Eq. 5-2
A + B + … + Z
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5-2
After determining Fa , select a wall type from Table 5.4A or Bthat has an adjustment factor, F, equal to or greater than Fa.Using the adjustment factor for this wall type, determine ifEq. 5-1 is satisfied. If it is not satisfied, select a wall typefrom Table 5.4A or B that has a slightly greater adjustmentfactor, F, and recompute Eq. 5-1. If necessary, repeat thisprocess until Eq. 5-1 is satisfied.
5.1.2 Length of Solid Wall for SeismicAll buildings assigned to Seismic Design Category A or B,and detached one- and two-family dwellings assigned toSeismic Design Category C shall have a total length of solidwall in each exterior wall line that complies with Section5.1.1 for wind. Multiple dwellings assigned to SeismicDesign Category C and all buildings assigned to SeismicDesign Category D0, D1 or D2 shall have a total length ofsolid wall in each exterior wall line that is equal to or greaterthan the larger of:
1. Section 5.1.1 for wind, and
2. This section (5.1.2) for seismic.
Multiple dwellings assigned to Seismic Design Category Cand all buildings assigned to Seismic Design Category D0, D1
or D2 shall have solid walls in each exterior wall line to resistlateral seismic forces. The site-appropriate Seismic DesignCategory and area of the building within the enclosing wallsshall be used to determine the unadjusted required totallength of solid wall in each exterior wall line from Table5.5A, B or C. Where the floor-to-ceiling height of a story isless than 10 feet (3.1 m), the unadjusted values determinedfrom Tables 5.5A, B and C are permitted to be reduced bymultiplying by the applicable factor from Table 5.6A or B.Where an exterior wall covering has an installed weight ofless than 11 psf (0.53 kN/m2), the unadjusted valuesdetermined from Tables 5.5A, B and C are permitted to bereduced by multiplying by the applicable factor from Table5.7. Where the ground snow load is equal to or greater than40 psf (1.92 kN/m2) and less than 70 psf (3.35 kN/m2), theunadjusted values determined from Tables 5.5A, B and C arepermitted to be reduced by multiplying by the applicablefactor from Table 5.8.
The unadjusted tabulated solid wall lengths in Tables 5.5A, Band C are based on a design strength of 840 pounds perfoot (12.26 kN/m) of length of solid wall segment. Toaccount for solid wall segments having a different designstrength, the actual length of an individual solid wallsegment complying with Section 5.2 that makes up a part of
a solid wall shall be adjusted based the amount of verticalreinforcement at its ends and other attributes. Adjustmentfactor, F, for individual solid wall segments shall bedetermined from Table 5.4A or B. In each exterior wall line ineach story, the adjusted lengths of solid wall segments beingconsidered (i.e., the product of the adjustment factor andthe length of the segment) shall satisfy Eq. 5-3.
F1A + F2B + … + Fn Z ≥ R5.6R5.7R5.8TL Eq. 5-3
Where A, B, … Z = actual length of individual solid wallsegments being considered in the exterior wall line beingevaluated (see Figure 5.2).
F1, F2 and Fn = adjustment factor applicable to solid wallsegment being considered from Table 5.4A or B
R5.6 = 1.0 or reduction factor for floor-to-ceiling heightfrom Table 5.6A or B
R5.7 = 1.0 or reduction factor for weight of exterior wallcovering from Table 5.7
R5.8 = 1.0 or reduction factor for snow load from Table5.8
TL = Unadjusted length of solid wall from Table 5.5A, B orC
Where the actual length of a solid wall segment is betweentwo lengths shown in Table 5.4A or B, or is greater than 48inches (1.2 m), use adjustment factor, F, for the next shorterseg ment length. No credit shall be taken for segments with alength less than required by Section 5.2.1.
The total length of solid wall after applying all reductionsand adjustments shall not be less than the greater of theminimum value and the length provided by two segmentscomplying with the minimum length requirements of Section5.2.1.
To facilitate compliance with Eq. 5-3, determine a requiredaverage adjustment factor, Fa , from Eq. 5-4.
R5.6R5.7R5.8TLFa = ------------------------------- Eq. 5-4
A + B + … + Z
After determining Fa , select a wall type from Table 5.4A or Bthat has an adjustment factor, F, equal to or greater than Fa .Using the adjustment factor for this wall type, determine ifEq. 5-3 is satisfied. If it is not satisfied, select a wall typefrom Table 5.4A or B that has a slightly greater adjustmentfactor, F, and recompute Eq. 5-3. If necessary, repeat thisprocess until Eq. 5-3 is satisfied.
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5-3
5.2 SOLID WALL SEGMENTSSolid wall segments that contribute to the required length ofsolid wall shall comply with this section. Reinforcement shallbe provided in accordance with Section 5.2.2 and Table 5.4Aor B. Solid wall segments shall extend the full story-heightwithout openings, other than openings for the purpose ofutilities and other building services passing through the wall.In flat walls and waffle-grid walls, such openings shall havean area of less than 30 square inches (19,355 mm2) with nodimension exceeding 6.25 inches (159 mm), and shall not belocated within 6 inches (152 mm) of the side edges of thesolid wall segment. In screen-grid walls, such openings shallbe located in the portion of the solid wall segment betweenhorizontal and vertical cores of concrete and opening sizeand location are not restricted provided no concrete isremoved.
5.2.1 Minimum Length of Solid Wall Segmentand Maximum Spacing
5.2.1.1 Seismic Design Categories A, B and C
In buildings assigned to Seismic Design Category A or B, anddetached one-and two-family dwellings assigned to SeismicDesign Category C, only solid wall segments equal to orgreater than 24 inches (610 mm) in length shall be includedin the total length of solid wall required by Section 5.1. Inaddition, no more than two solid wall segments equal to orgreater than 24 inches (610 mm) in length and less than 48inches (1.2 m) in length shall be included in the requiredtotal length of solid wall. The maximum clear opening widthbetween two solid wall segments not less than 24 inches(601 mm) in length shall be 18 feet (5.5 m). See Figure 5.2.
5.2.1.2 Seismic Design Category C
In multiple dwellings assigned to Seismic Design Category C,only solid wall segments equal to or greater than 36 inches(914 mm) in length shall be included in the total length ofsolid wall required by Section 5.1. The maximum clearopening width between two solid wall segments not lessthan 36 inches (914 mm) in length shall be 18 feet (5.5 m).See Figure 5.2.
5.2.1.3 Seismic Design Categories D0, D1 and D2
In all buildings assigned to Seismic Design Category D0, D1
or D2, only solid wall segments equal to or greater than48 inches (1.2 m) in length shall be included in the totallength of solid wall required by Section 5.1. The maximumclear opening width between two solid wall segments not
less than 48 inches (1.2 m) in length shall be 18 feet (5.5 m).See Figure 5.2.
5.2.2 Reinforcement in Solid Wall Segments
5.2.2.1 Horizontal Shear Reinforcement
Where adjustment factors from Table 5.4A or B based onhorizontal shear reinforcement being provided are used forbuildings assigned to Seismic Design Category A or B, anddetached one-and two-family dwellings assigned to SeismicDesign Category C, solid wall segments shall have horizontalreinforcement in accordance with Section 4.1.3 for multipledwellings assigned to Seismic Design Category C. Formultiple dwellings assigned to Seismic Design Category Cand all buildings assigned to Seismic Design Category D0, D1
or D2, use of adjustment factors based on horizontal shearreinforcement being provided is permitted in all cases. SeeSection 4.1.3 for horizontal reinforcement requirements formultiple dwellings assigned to Seismic Design Category Cand all buildings assigned to Seismic Design Category D0, D1
or D2.
Where adjustment factors from Table 5.4A or B based onhori zontal shear reinforcement being provided are used, themaximum spacing of horizontal reinforcement shall notexceed the smaller of one-half the length of the solid wallsegment, minus 2 inches (51 mm), the maximum spacingpermitted by Section 4.1.3, or 18 inches (457 mm). Hori -zontal shear reinforcement shall terminate in accordancewith Section 4.1.6.
5.2.2.2 Vertical Reinforcement
Vertical reinforcement applicable to the adjustment factor(s),F, from Table 5.4A or B that is used, shall be located at eachend of each solid wall segment in accordance with theapplicable detail in Figure 5.1. The additional verticalreinforcement required on each side of an opening bySection 7.1.2 is permitted to be used as reinforcement at theends of solid wall segments where installed in accordancewith the applicable detail in Figure 5.1. Where Section 7.1.2requires one No. 4 bar on each side of an opening, thereshall be not less than two No. 4 bars at each end of solidwall segments located as required by the applicable detail inFigure 5.1. Where Section 7.1.2 requires two No. 4 bars orone No. 5 bar on each side of an opening, there shall be notless than three No. 4 bars or two No. 5 bars at each end ofsolid wall seg ments located as required by the applicabledetail in Figure 5.1. One of the bars at each end of solid wallsegments shall be deemed to meet the requirements forvertical wall reinforcement required by Chapter 4.
Chapter 5 – Solid Walls for Resistance to Lateral Forces
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Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
5-4
5.2.2.3 Vertical Shear Reinforcement
Where adjustment factors from Table 5.4A or B based onhorizontal shear reinforcement being provided are used, thespacing of vertical reinforcement throughout the length ofthe segment shall not exceed the smaller of one-third thelength of the segment, the maximum spacing permitted bySection 4.1.3, or 18 inches (457 mm). Vertical shearreinforcement shall be continuous between stories in accor-dance with Section 4.1.5, and shall terminate in accordancewith Section 4.1.6. Vertical reinforcement required by thissection is permitted to be used for vertical reinforcementrequired by Section 4.1.2.
5.2.3 Solid Wall Segments at CornersAt all interior and exterior corners of exterior walls, a solidwall segment shall extend the full height of each wall story.The segment shall have the length required to develop thehorizontal reinforcement above and below the adjacentopening in tension in accordance with Section 2.5.4. For anexterior corner, the limiting dimension is measured on theoutside of the wall, and for an interior corner the limitingdimension is measured on the inside of the wall. See Section7.1. The length of a segment contributing to the requiredlength of solid wall shall comply with Section 5.2.1.
The end of a solid wall segment complying with theminimum length requirements of Section 5.2.1 shall belocated no more than 6 feet (1.8 m) from each corner.
5.3 MINIMUM WALL THICKNESS
5.3.1 Seismic Design Categories A, B and CIn buildings assigned to Seismic Design Category A or B,and in detached one-and two-family dwellings assigned toSeismic Design Category C, the minimum nominal thicknessof flat walls shall be 4 inches (102 mm).
5.3.2 Seismic Design Categories C, D0, D1 and D2
In multiple dwellings assigned to Seismic Design Category C,and in all buildings assigned to Seismic Design Category D0,D1 or D2, the minimum nominal thickness of walls shall be 6inches (152 mm). See Table 2.1.
5.4 COMMON WALL BETWEENATTACHED GARAGE AND DWELLINGWhere a building is composed of two or more rectangles inaccordance with Exception #1 to Section 1.2.2, item 1, eachrectangle shall be considered separately and the lengths ofsolid wall to satisfy the requirements of Section 5.1 shall bedetermined separately for the two rectangles. Beforeapplying the minimum length requirements to the commonwall between the garage and dwelling, sum the calculatedlengths and then determine if the minimum requirementsare met.
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5-5
Chapter 5 – Solid Walls for Resistance to Lateral Forces
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Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
5-6
Table 5.1A. Unadjusted Length of Solid Wall, TL, Required in Each Exterior Endwall for Wind Perpendicular to Ridge One Story or Top Story of Two-Story1,3,4,5,6,7
Sidewalllength,L (ft)
Endwalllength,W (ft)
Roofslope
Unadjusted length of solid wall, TL, required in endwalls for wind perpendicular to ridge, (ft)85B 90B 100B 110B 120B 130B 140B 150B 166B 179B 192B
Minimum285C 90C 100C 110C 120C 130C 140C 150C 163C
85D 90D 100D 110D 120D 130D 140D 150DVelocity pressure, (psf)
11.51 12.90 15.95 19.28 22.94 26.92 31.79 37.41 43.90 50.91 58.45
15
15
≤1 in 125 in 127 in 12
12 in 12
30
≤1 in 125 in 127 in 12
12 in 12
45
≤1 in 125 in 127 in 12
12 in 12
60
≤1 in 125 in 127 in 12
12 in 12
30
15
≤1 in 125 in 127 in 12
12 in 12
30
≤1 in 125 in 127 in 12
12 in 12
45
≤1 in 125 in 127 in 12
12 in 12
60
≤1 in 125 in 127 in 12
12 in 12
60
15
≤1 in 125 in 127 in 12
12 in 12
30
≤1 in 125 in 127 in 12
12 in 12
45
≤1 in 125 in 127 in 12
12 in 12
60
≤1 in 125 in 127 in 12
12 in 12
0.901.251.752.800.901.252.434.520.901.253.126.250.901.253.807.971.612.243.154.901.612.244.307.791.612.245.44
10.691.612.246.59
13.582.994.155.919.052.994.157.97
14.253.114.31
10.2419.843.224.47
12.5725.61
1.011.401.963.131.011.402.735.071.011.403.497.001.011.404.268.941.802.513.535.491.802.514.828.741.802.516.10
11.981.802.517.39
15.223.354.656.63
10.143.354.658.94
15.973.484.84
11.4722.243.615.01
14.0928.70
1.251.732.433.871.251.733.376.271.251.734.328.661.251.735.26
11.052.233.104.376.792.233.105.96
10.802.233.107.54
14.812.233.109.13
18.824.145.758.19
12.544.145.75
11.0519.744.305.98
14.1927.494.466.19
17.4235.49
1.512.092.934.681.512.094.087.571.512.095.22
10.471.512.096.36
13.362.703.745.288.212.703.747.20
13.062.703.749.12
17.902.703.74
11.0422.755.006.959.90
15.165.006.95
13.3623.865.207.23
17.1533.235.397.49
21.0542.90
1.802.493.495.571.802.494.859.011.802.496.21
12.451.802.497.57
15.893.214.456.289.773.214.458.57
15.533.214.45
10.8521.303.214.45
13.1427.075.958.27
11.7818.035.958.27
15.8928.406.198.60
20.4039.546.428.91
25.0551.04
2.112.924.106.542.112.925.69
10.582.112.927.29
14.612.112.928.89
18.653.775.237.37
11.463.775.23
10.0518.233.775.23
12.7325.003.775.23
15.4131.776.989.70
13.8321.166.989.70
18.6533.327.26
10.0923.9446.407.53
10.4629.3959.90
2.493.454.847.722.493.456.72
12.492.493.458.61
17.262.493.45
10.4922.024.456.178.71
13.534.456.17
11.8721.534.456.17
15.0429.524.456.17
18.2037.518.25
11.4616.3324.998.25
11.4622.0239.358.58
11.9228.2854.808.89
12.3534.7170.73
2.934.065.699.092.934.067.91
14.702.934.06
10.1320.312.934.06
12.3525.925.237.26
10.2415.935.237.26
13.9725.335.237.26
17.7034.745.237.26
21.4244.159.70
13.4819.2129.419.70
13.4825.9246.3110.1014.0233.2764.4810.4714.5340.8583.24
3.444.776.68
10.663.444.779.28
17.253.444.77
11.8923.833.444.77
14.4930.416.148.53
12.0218.696.148.53
16.3929.736.148.53
20.7740.776.148.53
25.1451.8111.3915.8222.5534.5111.3915.8230.4154.3411.8516.4539.0575.6712.2817.0547.9397.68
3.995.537.75
12.363.995.53
10.7720.003.995.53
13.7827.643.995.53
16.8035.277.129.89
13.9421.677.129.89
19.0134.477.129.89
24.0847.287.129.89
29.1560.0813.2018.3526.1540.0213.2018.3535.2763.0213.7419.0845.2887.7514.2419.7755.59
113.28
4.586.358.89
14.204.586.35
12.3622.964.586.35
15.8331.734.586.35
19.2940.508.18
11.3516.0124.888.18
11.3521.8339.588.18
11.3527.6554.288.18
11.3533.4768.9815.1621.0730.0245.9515.1621.0740.4972.3515.7721.9151.99
100.7516.3522.7063.82
130.05
0.981.431.642.211.092.012.423.571.212.593.214.931.333.163.996.291.932.753.124.142.143.784.526.572.354.815.929.002.565.847.32
11.433.835.376.078.004.237.318.71
12.574.639.25
11.3517.145.03
11.1913.9921.71
For SI: 1 foot = 0.3048 m; 1 inch = 25.4 mm; 1 mph = 0.4470 m/sFor Notes see page 5-7.
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5-7
Chapter 5 – Solid Walls for Resistance to Lateral Forces
Notes for Tables 5.1A, 5.1B and 5.1C.1 Tabulated values were derived by calculating design wind pressures in accordance with Figure 6-10 of ASCE 7 for a building with a mean roof height
of 35 feet (10.7 m). For wind perpendicular to the ridge, the effects of a 2-foot (610 mm) overhang on each endwall are included. The designpressures were used to calculate forces to be resisted by solid wall segments in each sidewall or endwall, as appropriate. The forces to be resisted byeach wall line were then divided by the design strength (840 pounds per foot of length (12.26 kN/m)) of the default solid wall segment (see Note 5).The actual mean roof height of the building shall not exceed the least horizontal dimension of the building.
2 Tabulated values in the “minimum” column are based on the requirement of Section 6.1.4.1 of ASCE 7 that the main wind-force resisting system bedesigned for a minimum service level force of 10 psf (0.48 kN/m2) multiplied by the area of the building projected onto a vertical plane normal to theassumed wind direction. Tabulated values in shaded cells are less than the “minimum” value. Where the minimum controls, it is permitted to bereduced in accordance with Notes 4 and 5; however, no reduction is permitted if the mean roof height is less than 35 feet (10.7 m). See Note 3 andSection 5.1.1.
3 For buildings with a mean roof height of less than 35 feet (10.7 m), tabulated values are permitted to be reduced by multiplying by the appropriatefactor from Table 5.2. The reduced value shall not be less than the “minimum” value shown in the table.
4 Tabulated values for “one story or top story of two-story” are based on a floor-to-ceiling height of 10 feet (3.0 m). Tabulated values for “first story oftwo-story” are based on floor-to-ceiling heights of 10 feet (3.0 m) each for the first and second story. For floor-to-ceiling heights less than assumed,use the values in Table 5.1A, B or C, or multiply the value in the table by the reduction factor from Table 5.3.
5 Tabulated values are based on the design shear strength (840 pounds per foot of solid wall segment (12.26 kN/m)) of a 6-inch (152 mm) screen-gridwall with two or more 24-inch (610 mm) long solid wall segments constituting the total length of solid wall required by the table. The solid wallsegment is constructed with concrete having a specified compressive strength of not less than 2,500 psi (17.2 MPa), and each end of each 24-inch(610 mm) long solid wall segment has three No. 4 bars with a yield strength of 40,000 psi (280 MPa) arranged in accordance with detail 4 of Figure5.1. For different solid wall segments, segments equal to or greater than 36 inches (914 mm) in length, a different number, yield strength, and/orarrangement of bars, higher strength concrete, and for flat and waffle-grid walls, adjust tabulated values by multiplying by the appropriateadjustment factor from Table 5.4A or B. See Note 3.
6 The reduction factors in Tables 5.2 and 5.3, and adjustments factors in Tables 5.4A and B are permitted to be compounded, subject to the limitationsof Note 2. However, the minimum number and minimum length of solid walls segments in each wall line shall comply with Sections 5.1 and 5.2.1,respectively.
7 For intermediate values of sidewall length, endwall length, roof slope and basic wind speed, use the next higher value, or determine by interpolation.
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Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
5-8
Table 5.1B. Unadjusted Length of Solid Wall, TL, Required in Each Exterior Endwall for Wind Perpendicular to RidgeFirst Story of Two-Story1,3,4,5,6,7
Sidewalllength,L (ft)
Endwalllength,W (ft)
Roofslope
Unadjusted length of solid wall, TL, required in endwalls for wind perpendicular to ridge, (ft)85B 90B 100B 110B 120B 130B 140B 150B 166B 179B 192B
Minimum285C 90C 100C 110C 120C 130C 140C 150C 163C
85D 90D 100D 110D 120D 130D 140D 150DVelocity pressure, (psf)
11.51 12.90 15.95 19.28 22.94 26.92 31.79 37.41 43.90 50.91 58.45
15
15
≤1 in 125 in 127 in 12
12 in 12
30
≤1 in 125 in 127 in 12
12 in 12
45
≤1 in 125 in 127 in 12
12 in 12
60
≤1 in 125 in 127 in 12
12 in 12
30
15
≤1 in 125 in 127 in 12
12 in 12
30
≤1 in 125 in 127 in 12
12 in 12
45
≤1 in 125 in 127 in 12
12 in 12
60
≤1 in 125 in 127 in 12
12 in 12
60
15
≤1 in 125 in 127 in 12
12 in 12
30
≤1 in 125 in 127 in 12
12 in 12
45
≤1 in 125 in 127 in 12
12 in 12
60
≤1 in 125 in 127 in 12
12 in 12
For SI: 1 foot = 0.3048 m; 1 inch = 25.4 mm; 1 mph = 0.4470 m/sFor Notes see page 5-7.
2.603.613.774.812.603.614.456.542.603.615.148.272.603.615.829.994.656.466.948.694.656.468.09
11.584.656.469.23
14.484.656.46
10.3817.378.62
11.9813.1816.328.62
11.9815.2521.528.97
12.4617.6727.279.30
12.9120.1433.19
2.924.054.235.402.924.054.997.332.924.055.769.272.924.056.52
11.205.217.247.789.745.217.249.06
12.985.217.24
10.3516.225.217.24
11.6319.479.67
13.4314.7818.299.67
13.4317.0924.1210.0613.9719.8030.5610.4314.4722.5837.19
3.615.005.236.673.615.006.179.063.615.007.12
11.463.615.008.06
13.856.458.959.62
12.046.458.95
11.2116.056.458.95
12.7920.066.458.95
14.3824.0711.9516.6118.2722.6211.9516.6121.1329.8212.4317.2724.4837.7912.8917.9027.9145.99
4.366.056.328.064.366.057.46
10.964.366.058.60
13.854.366.059.75
16.747.79
10.8211.6214.557.79
10.8213.5419.407.79
10.8215.4624.257.79
10.8217.3829.1014.4520.0722.0827.3414.4520.0725.5436.0515.0320.8829.5945.6815.5821.6333.7455.59
5.197.207.529.605.197.208.88
13.045.197.20
10.2416.485.197.20
11.6019.929.27
12.8713.8317.329.27
12.8716.1223.089.27
12.8718.4028.859.27
12.8720.6934.6217.1923.8826.2832.5317.1923.8830.3842.8917.8824.8435.2154.3518.5425.7440.1566.14
6.098.458.82
11.266.098.45
10.4215.306.098.45
12.0119.346.098.45
13.6123.3710.8815.1016.2320.3210.8815.1018.9127.0910.8815.1021.5933.8610.8815.1024.2740.6320.1728.0330.8338.1720.1728.0335.6650.3320.9929.1541.3263.7821.7630.2047.1177.62
7.199.97
10.4113.307.199.97
12.3018.077.199.97
14.1822.837.199.97
16.0727.6012.8517.8319.1724.0012.8517.8322.3331.9912.8517.8325.5039.9812.8517.8328.6747.9823.8233.1036.4145.0823.8233.1042.1159.4324.7834.4248.7975.3125.6935.6755.6491.66
8.4711.7412.2615.658.47
11.7414.4721.268.47
11.7416.6926.878.47
11.7418.9132.4815.1220.9922.5628.2415.1220.9926.2837.6415.1220.9930.0147.0515.1220.9933.7356.4628.0338.9542.8553.0528.0338.9549.5569.9429.1740.5157.4288.6330.2441.9765.47
107.86
9.9413.7714.3818.369.94
13.7716.9924.959.94
13.7719.5931.539.94
13.7722.1938.1217.7424.6326.4733.1417.7424.6330.8444.1817.7424.6335.2155.2117.7424.6339.5966.2532.8945.7150.2862.2532.8945.7158.1582.0834.2347.5367.38
104.0035.4849.2676.83
126.58
11.5215.9716.6821.3011.5215.9719.7028.9311.5215.9722.7236.5711.5215.9725.7444.2020.5728.5630.7038.4320.5728.5635.7751.2320.5728.5640.8464.0320.5728.5645.9176.8338.1553.0158.3172.1938.1553.0167.4395.1839.6955.1278.14
120.6141.1557.1289.10
146.79
13.2318.3419.1524.4513.2318.3422.6133.2213.2318.3426.0841.9813.2318.3429.5550.7523.6232.7935.2444.1223.6232.7941.0658.8223.6232.7946.8873.5123.6232.7952.7188.2143.8060.8666.9582.8843.8060.8677.42
109.2845.5763.2989.71
138.4747.2465.58
102.29168.53
2.593.053.263.832.713.634.045.192.834.204.836.552.954.785.617.905.165.986.357.385.387.017.769.815.598.049.16
12.245.809.08
10.5614.6710.3011.8512.5414.4810.7013.7915.1819.0511.1015.7317.8223.6211.5017.6720.4628.19
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Chapter 5 – Solid Walls for Resistance to Lateral Forces
Table 5.1C. Unadjusted Length of Solid Wall, TL, Required in Each Exterior Sidewall for Wind Parallel to Ridge1,3,4,5,6,7
Sidewalllength,L (ft)
Endwalllength,W (ft)
Roofslope
Unadjusted length of solid wall, TL, required in sidewalls for wind parallel to ridge, (ft)85B 90B 100B 110B 120B 130B 140B 150B 166B 179B 192B
Minimum285C 90C 100C 110C 120C 130C 140C 150C 163C85D 90D 100D 110D 120D 130D 140D 150D
One story or top story of two-story
≤ 30
15
≤1 in 125 in 127 in 12
12 in 12
30
≤1 in 125 in 127 in 12
12 in 12
45
≤1 in 125 in 127 in 12
12 in 12
60
≤1 in 125 in 127 in 12
12 in 12
60
45
≤1 in 125 in 127 in 12
12 in 12
60
≤1 in 125 in 127 in 12
12 in 12First story of two-story
≤ 30
15
≤1 in 125 in 127 in 12
12 in 12
30
≤1 in 125 in 127 in 12
12 in 12
45
≤1 in 125 in 127 in 12
12 in 12
60
≤1 in 125 in 127 in 12
12 in 12
60
45
≤1 in 125 in 127 in 12
12 in 12
60
≤1 in 125 in 127 in 12
12 in 12
For SI: 1 foot = 0.3048 m; 1 inch = 25.4 mm; 1 mph = 0.4470 m/sFor Notes see page 5-7.
0.951.131.211.431.772.382.663.432.653.984.586.253.595.936.999.922.774.154.786.513.866.317.43
10.51
1.061.261.351.601.982.672.983.852.974.465.147.014.036.657.83
11.123.114.665.367.304.327.088.32
11.78
1.311.561.671.982.453.303.694.763.675.516.358.674.988.229.69
13.753.845.766.639.035.358.75
10.2914.56
1.591.882.022.392.963.994.465.754.436.667.68
10.486.029.93
11.7116.624.656.968.01
10.916.46
10.5712.4417.60
1.892.242.402.853.534.755.316.845.277.939.14
12.477.16
11.8213.9319.775.538.289.53
12.987.69
12.5814.8020.94
2.222.632.823.344.145.576.238.036.199.31
10.7214.638.40
13.8716.3523.216.499.72
11.1815.239.02
14.7617.3724.57
2.623.113.333.954.896.587.359.487.31
10.9912.6617.289.92
16.3819.3127.407.66
11.4813.2117.9910.6517.4420.5129.02
3.083.663.924.645.757.758.65
11.158.60
12.9314.9020.3311.6819.2722.7232.259.02
13.5015.5421.1712.5420.5224.1434.15
3.624.294.605.456.759.09
10.1513.0910.0915.1817.4823.8613.7022.6226.6637.8410.5815.8518.2424.8414.7124.0828.3340.07
4.194.985.336.327.83
10.5411.7715.1811.7017.6020.2727.6715.8926.2330.9243.8812.2718.3821.1528.8117.0627.9232.8546.47
4.815.716.127.258.99
12.1013.5217.4313.4420.2123.2831.7618.2430.1135.5050.3814.0921.1024.2833.0819.5932.0637.7153.35
0.901.081.171.391.902.622.953.862.994.625.367.394.187.078.38
12.002.994.625.367.394.187.078.38
12.00
2.652.832.913.134.815.425.706.476.998.328.93
10.609.23
11.5712.6315.567.348.729.34
11.089.94
12.4013.5116.59
2.973.173.263.515.396.086.397.257.839.33
10.0111.8810.3512.9714.1517.448.229.77
10.4712.4111.1413.8915.1418.59
3.673.924.034.346.677.527.908.979.69
11.5312.3714.6912.7916.0317.5021.5610.1712.0812.9515.3513.7717.1818.7222.99
4.444.744.875.258.069.099.55
10.8411.7113.9414.9517.7515.4619.3821.1526.0612.2914.6015.6518.5516.6520.7622.6327.79
5.285.645.806.249.59
10.8111.3712.9013.9316.5917.7921.1318.4023.0625.1731.0114.6217.3718.6222.0719.8124.7026.9233.06
6.206.626.807.32
11.2512.6913.3415.1416.3519.4720.8824.7921.5927.0629.5436.3917.1620.3921.8525.9023.2528.9931.6038.80
7.327.818.038.65
13.2914.9815.7517.8819.3122.9924.6629.2725.5031.9534.8842.9820.2624.0725.8130.5927.4534.2437.3145.82
8.629.199.46
10.1815.6417.6318.5421.0422.7227.0529.0234.4530.0037.6041.0550.5723.8428.3330.3736.0032.3140.2943.9153.92
10.1110.7911.1011.9418.3520.6921.7524.6926.6631.7534.0540.4335.2144.1248.1759.3527.9833.2535.6442.2437.9147.2851.5363.27
11.7312.5112.8713.8521.2823.9925.2228.6330.9236.8139.4946.8840.8351.1755.8668.8332.4538.5541.3348.9943.9754.8359.7573.37
13.4614.3614.7715.9024.4327.5528.9632.8735.5042.2745.3453.8346.8858.7564.1379.0237.2544.2647.4556.2450.4862.9568.6084.24
2.522.702.793.015.145.866.197.107.859.48
10.2112.2510.6513.5414.8518.487.859.48
10.2112.2510.6513.5414.8518.48
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Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
5-10
Table 5.2. Reduction Factor, R5.2 , for Buildings with Mean Roof Height Less than 35 Feet1
Mean roof height – (ft)2,3Wind exposure category
B C D
≤ 15 0.96 0.84 0.87
20 0.96 0.89 0.91
25 0.96 0.93 0.94
30 0.96 0.97 0.98
35 1.00 1.00 1.00
For SI: 1 foot = 0.3048 m1 See note 2 to Tables 5.1A, B and C for application of reduction factors in this table.2 For intermediate values of mean roof height, use the factor for the next greater height, or determine by interpolation. This reduction is not permitted
for “minimum” values.3 Mean roof height is the average of the roof eave height and height of the highest point on the roof surface, except that for roof slopes of less than or
equal to 2.12 in 12 (10 degrees), the mean roof height is permitted to be taken as the roof eave height.
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Chapter 5 – Solid Walls for Resistance to Lateral Forces
Story underconsideration
Floor-to-ceilingheight, (ft)3
Endwall length,W (ft)
Roof slope Reduction factor, R5.3
Endwalls – for wind perpendicular to ridge
One story ortop story oftwo-story
8'
15
≤ 5 in 12 0.83
7 in 12 0.90
12 in 12 0.94
60
≤ 5 in 12 0.83
7 in 12 0.95
12 in 12 0.98
First story oftwo-story
16' combinedfirst and second
story
15
≤ 5 in 12 0.83
7 in 12 0.86
12 in 12 0.89
60
≤ 5 in 12 0.83
7 in 12 0.91
12 in 12 0.95
Sidewalls – for wind parallel to ridge
One story ortop story oftwo-story
8'
15
≤ 1 in 12 0.84
5 in 12 0.87
7 in 12 0.88
12 in 12 0.89
60
≤ 1 in 12 0.86
5 in 12 0.92
7 in 12 0.93
12 in 12 0.95
First story oftwo-story
16' combinedfirst and second
story
15
≤ 1 in 12 0.83
5 in 12 0.84
7 in 12 0.85
12 in 12 0.86
60
≤ 1 in 12 0.84
5 in 12 0.87
7 in 12 0.88
12 in 12 0.90
Table 5.3. Reduction Factor, R5.3 , for Floor-to-Ceiling Wall Heights Less than 10 Feet1,2
For SI: 1 foot = 0.3048 m1 See note 4 to Tables 5.1A, B and C for application of reduction factors in this table.2 For intermediate values of endwall length, and/or roof slope, use the next higher value, or determine by interpolation.3 Tabulated values in Tables 5.1A, B and C for “one story or top story of two-story” are based on a floor-to-ceiling height of 10 feet (3.0 m). Tabulated
values in Tables 5.1A, B and C for “first story of two-story” are based on floor-to-ceiling heights of 10 feet (3.0 m) each for the first and second story.For floor to ceiling heights between those shown in this table and those assumed in Tables 5.1A, B and C, use the solid wall lengths in Table 5.1A, Bor C, or determine the reduction factor by interpolating between 1.0 and the factor shown in this table.
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Table 5.4A. Adjustment Factor, F, and Layout of Reinforcement at Each End of Solid Wall Segments for Flat Walls1
Nominalthickness of
flat wall – (in.)
Length ofsolid wallsegment2
– (in.)
Vertical bars at each endof solid wall segment
Reinforcementlayout detail No. –
see Figure 5.1
Adjustment factor, F, for length of solid wallHorizontal shear reinforcement provided?
No3 Yes4
Number of Bars Bar size No. 40,0005,7 60,0005,7 40,0005,7 60,0005
All others7 SDC D6,8,9
49
24
36
48
6
24
36
48
8
24
36
48
10
24
36
48
NPNPNPNPNPNPNPNPNPNPNP
1.993.764.045.662.113.063.266.242.183.193.376.532.013.964.125.076.037.632.133.163.294.116.488.382.193.263.394.275.038.752.023.125.007.317.59
10.922.143.314.088.038.35
12.212.193.414.246.296.55
12.46
2.423.283.602.003.764.045.612.094.014.276.051.973.713.995.542.103.043.236.162.173.173.356.472.003.924.085.005.947.472.123.143.274.086.428.272.183.253.384.245.008.672.013.104.957.207.47
10.642.133.304.057.958.27
12.022.193.404.226.256.50
12.72
1.252.292.511.361.932.083.911.412.042.184.161.341.912.053.851.422.062.193.161.462.142.263.291.352.002.082.574.085.191.422.122.212.763.274.241.462.182.272.863.384.411.362.092.534.955.157.471.432.222.744.054.228.271.472.282.844.224.396.50
1.561.481.561.671.611.671.611.721.681.721.681.972.502.582.502.102.652.702.652.172.722.762.722.003.523.523.433.523.432.123.143.273.633.683.632.183.253.383.723.773.722.013.104.244.244.244.242.133.304.054.524.524.522.193.404.224.674.674.67
1.251.481.561.361.611.671.611.411.681.721.681.341.912.052.501.422.062.192.651.462.142.262.721.352.002.082.573.523.431.422.122.212.763.273.631.462.182.272.863.383.721.362.092.534.244.244.241.432.222.744.054.224.521.472.282.844.224.394.67
12112121212343434343434353656353656353656337878337878337878
44544554455445544554455445455445455445455454455454455454455
23223232323232323232323232434232434232434224646224646224646
For SI: 1 inch = 25.4 mm; 1,000 psi = 6.895 MPa
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Chapter 5 – Solid Walls for Resistance to Lateral Forces
1 See note 5 to Tables 5.1A, B and C for application of adjustment factors in this table.2 For intermediate lengths of solid wall segments or segments that are longer than the maximum given in the table, use adjustment factor for next
shorter length given in table.3 For all buildings assigned to Seismic Design Category A or B, and detached one-and two-family dwellings assigned to Seismic Design Category C, use
the adjustment factor for length of solid wall without horizontal shear reinforcement.4 Where buildings assigned to Seismic Design Category A or B, and detached one-and two-family dwellings assigned to Seismic Design Category C are
provided with horizontal reinforcement in accordance with Section 4.1.3 for multiple dwellings assigned to Seismic Design Category C, use of theadjustment factor for length of solid wall with horizontal shear reinforcement is permitted. For multiple dwellings assigned to Seismic Design CategoryC and all buildings assigned to Seismic Design Category D0, D1 or D2, use the adjustment factor for length of solid wall with shear reinforcement. SeeSection 4.1.3 for required reinforcement.
5 Yield strength of vertical wall reinforcement at ends of solid wall segments.6 Use this column for buildings assigned to Seismic Design Category D0, D1 or D2 because use of steel with minimum yield strength of 60,000 psi (420
MPa) is required. See Section 4.1.3.7 Values in this column are based on concrete with a specified compressive strength, ø, of 2,500 psi (17.2 MPa). Where concrete with ø of not less than
3,000 psi (20.7 MPa) is used, values in shaded cells are permitted to be increased by multiplying by 1.10. See Note 8. For buildings assigned to SeismicDesign Category D, use this column for determining the adjustment factors for solid wall lengths for wind loads in Tables 5.1A, B and C.
8 Adjustment factors in this column are based on concrete with a specified compressive strength, ø , of 3,000 psi (20.7 MPa). See Section 4.1.4.9 NP = Not permitted. 4-inch (102 mm) flat walls are not permitted for multiple dwellings assigned to Seismic Design Category C and all buildings
assigned to Seismic Design Category D0, D1 or D2. See Section 5.3.
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Table 5.4B. Adjustment Factor, F, and Layout of Reinforcement at Each End of Solid Wall Segments forWaffle-Grid and Screen-Grid Walls1,9
Nominal thickness andtype of wall
– (in.)
Length of solid wallsegment2
– (in.)
Vertical bars at each endof solid wall segment Reinforcement
layout detail No. –see Figure 5.1
Adjustment factor, F, for length of solid wallHorizontal shear reinforcement provided?
No3 Yes4
Number of Bars Bar size No.40,000 and60,0005,7 40,0005,7
60,0005
All others7 SDC D6,8
6 waffle
24
36
48
8 waffle
24
36
48
6 screen
24
36
48
2.653.764.045.662.114.094.346.242.183.193.376.532.683.964.125.076.036.262.134.224.395.486.486.612.193.263.395.696.716.792.653.764.045.252.114.094.345.572.183.193.375.72
2.633.713.995.542.104.054.306.162.173.173.356.472.663.924.085.005.947.142.124.194.365.446.427.542.183.253.385.666.677.752.633.713.995.542.104.054.306.162.173.173.356.47
1.342.542.733.851.422.062.194.211.462.142.263.291.352.662.773.424.085.191.422.122.212.764.365.651.462.182.272.863.385.881.342.542.733.851.422.062.194.211.462.142.263.29
1.221.181.221.181.281.251.281.251.311.291.311.291.221.221.221.191.221.191.281.281.281.261.281.261.311.311.311.291.311.291.031.001.031.001.081.061.081.061.101.091.101.09
343434343434353656353656353656343434343434
445544554455445455445455445455445544554455
232323232323232434232434232434232323232323
For SI: 1 inch = 25.4 mm; 1,000 psi = 6.895 MPa
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Chapter 5 – Solid Walls for Resistance to Lateral Forces
1 See note 5 to Tables 5.1A, B and C for application of adjustment factors in this table.2 For intermediate lengths of solid wall segments, use adjustment factor for next shorter length given in table.3 For all buildings assigned to Seismic Design Category A or B, and detached one-and two-family dwellings assigned to Seismic Design Category C, use
the adjustment factor for length of solid wall without horizontal shear reinforcement.4 Where buildings assigned to Seismic Design Category A or B, and detached one-and two-family dwellings assigned to Seismic Design Category C are
provided with horizontal reinforcement in accordance with Section 4.1.3 for multiple dwellings assigned to Seismic Design Category C, use of theadjustment factor for length of solid wall with horizontal shear reinforcement is permitted. For multiple dwellings assigned to Seismic Design CategoryC and all buildings assigned to Seismic Design Category D0, D1 or D2, use the adjustment factor for length of solid wall with shear reinforcement. SeeSection 4.1.3 for required reinforcement.
5 Yield strength of vertical wall reinforcement at ends of solid wall segments.6 Use this column for buildings assigned to Seismic Design Category D0, D1 or D2 because use of steel with minimum yield strength of 60,000 psi (420
MPa) is required. See Section 4.1.3.7 Values in this column are based on concrete with a specific compressive strength, ø, of 2,500 psi (17.2 MPa). Where concrete with ø of not less than
3,000 psi (20.7 MPa) is used, values in shaded cells are permitted to be increased by multiplying by 1.10. See Note 8.8 Adjustment factors in this column are based on concrete with a specified compressive strength, ø, of 3,000 psi (20.7 MPa). See Section 4.1.4. 9 Each end of each solid wall segment shall have rectangular flanges. In the through-the-wall dimension, the flange shall not be less than 5.5 inches
(140 mm) for 6-inch (152 mm) nominal waffle- and screen-grid forms, and not less than 7.5 inches (191 mm) for 8-inch (203 mm) nominal waffle-grid forms. In the in-plane dimension, flanges shall be long enough to accommodate the vertical reinforcement required by the layout detail selectedfrom Figure 5.1and provide the cover required by Section 2.5.1. If necessary to achieve the required dimensions, form material shall be removed orflat wall forms are permitted to be used.
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Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
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Table 5.5A. Unadjusted Length of Solid Wall, TL, Required in Each Exterior Endwall and Sidewall for Seismic ResistanceOne Story or Top story of Two-Story1,2,4,5,7,8
SeismicDesign
Category
Groundsnowload6,
pg, – (psf)
Wallgroup3
Unadjusted length of solid wall, TL, required in each exterior wall line – (ft)
Area of building within exterior walls projected onto a horizontal plane – (sq ft)
200 300 400 600 800 1000 1500 2000 2500 3000 4000
CSDS = 0.50
< 40
1
2
3
4
≥ 40 – 70
1
2
3
4
D0
SDS = 0.67
< 40
1
2
3
4
≥ 40 – 70
1
2
3
4
D1
SDS = 0.83
< 40
1
2
3
4
≥ 40 – 70
1
2
3
4
D2
SDS = 1.00
< 40
1
2
3
4
≥ 40 – 70
1
2
3
4
10.03
11.52
13.32
15.19
12.50
13.99
15.79
17.66
10.75
12.35
14.28
16.28
13.40
15.00
16.93
18.93
13.32
15.30
17.69
20.17
16.59
18.58
20.97
23.45
16.04
18.44
21.31
24.30
19.99
22.39
25.26
28.26
8.54
9.88
11.49
13.16
10.54
11.88
13.49
15.16
9.15
10.59
12.31
14.11
11.30
12.73
14.46
16.25
11.33
13.12
15.25
17.48
13.99
15.77
17.91
20.14
13.66
15.80
18.38
21.06
16.86
19.00
21.58
24.26
14.23
16.11
18.38
20.74
18.09
19.98
22.24
24.60
15.25
17.27
19.70
22.23
19.39
21.41
23.84
26.37
18.89
21.40
24.41
27.54
24.02
26.53
29.54
32.67
22.76
25.78
29.41
33.18
28.94
31.96
35.58
39.36
11.46
13.10
15.07
17.11
14.40
16.04
18.00
20.05
12.29
14.05
16.15
18.35
15.44
17.19
19.30
21.49
15.22
17.40
20.01
22.73
19.12
21.30
23.91
26.63
18.34
20.96
24.11
27.38
23.04
25.66
28.80
32.08
4.56
5.41
6.44
7.51
5.42
6.27
7.30
8.37
4.89
5.80
6.90
8.05
5.81
6.72
7.82
8.97
6.05
7.19
8.55
9.97
7.19
8.33
9.69
11.11
7.29
8.66
10.31
12.02
8.67
10.04
11.68
13.39
3.78
4.53
5.42
6.35
4.45
5.19
6.08
7.01
4.06
4.85
5.81
6.81
4.77
5.56
6.52
7.52
5.03
6.01
7.20
8.43
5.91
6.89
8.08
9.31
6.06
7.25
8.67
10.16
7.11
8.30
9.73
11.22
6.97
8.13
9.53
10.98
8.50
9.66
11.06
12.51
7.47
8.72
10.22
11.78
9.11
10.36
11.86
13.41
9.25
10.80
12.66
14.59
11.29
12.83
14.69
16.62
11.15
13.01
15.25
17.58
13.60
15.46
17.69
20.02
5.28
6.24
7.38
8.58
6.34
7.29
8.44
9.63
5.66
6.69
7.92
9.19
6.79
7.82
9.04
10.32
7.02
8.28
9.81
11.39
8.41
9.68
11.20
12.79
8.45
9.98
11.81
13.72
10.14
11.66
13.50
15.41
2.47
3.00
3.64
4.30
2.83
3.36
4.00
4.66
2.64
3.21
3.90
4.61
3.03
3.60
4.29
5.00
3.28
3.98
4.83
5.71
3.75
4.46
5.31
6.19
3.95
4.80
5.82
6.88
4.52
5.37
6.40
7.46
1.94
2.38
2.91
3.46
2.20
2.64
3.16
3.71
2.08
2.55
3.12
3.70
2.36
2.83
3.39
3.98
2.58
3.16
3.86
4.59
2.92
3.50
4.20
4.93
3.11
3.81
4.65
5.53
3.52
4.22
5.06
5.94
2.94
3.55
4.28
5.04
3.40
4.01
4.74
5.51
3.15
3.80
4.59
5.41
3.64
4.30
5.08
5.90
3.90
4.71
5.68
6.70
4.51
5.33
6.30
7.31
4.70
5.68
6.85
8.07
5.44
6.42
7.59
8.81
For SI: 1 ft. = 0.3048 m; 1 sq. ft. = 0.0929 m2; 1 psf = 0.0479 kN/m2
O85573 1.qxd:FPO 85573 1 1/24/08 10:55 AM Page 5-16
5-17
Chapter 5 – Solid Walls for Resistance to Lateral Forces
Notes for Tables 5.5A, 5.5B and 5.5C1 Tabulated values are base on a building with an aspect ratio of 2:1, which is the maximum permitted by Section 1.2.2, item 1. Values include the
contribution of the mass of a 2-foot (610 mm) overhang on all edges of the roof. The gable portion of endwalls shall be of light-framed constructionin accordance with Section 1.2.2, item 5.
2 For one story buildings, tabulated values in Table 5.5A are permitted to be reduced by multiplying by 0.91.3 Wall group 1 includes 6-inch (152 mm) waffle-grid and 6-inch (152 mm) screen-grid. Wall group 2 includes 6-inch (152 mm) flat and 8-inch (203 mm)
waffle-grid. Wall group 3 is 8-inch (203 mm) flat, and wall group 4 is 10-inch (254 mm) flat. See Table 2.1 for minimum dimensions. See Section 5.3.2for minimum thicknesses.
4 Tabulated values are based on walls with floor to ceiling heights of 10 feet (3.0 m). For shorter walls, tabular values are permitted to be reduced bymultiplying by factors determined from Table 5.6A or B. See Notes 5, 6 and 7.
5 Tabulated values are based on an exterior wall covering having an installed weight of 11 psf (0.53 kN/m2) (e.g., 7⁄8-inch (22 mm) cement stucco). Forexterior wall coverings with an installed weight of less than 11 psf (0.53 kN/m2), tabular values are permitted to be reduced by multiplying by factorsdetermined from Table 5.7. See Notes 4, 6 and 7.
6 Tabulated values in the table for ground snow load between 40 (1.92 kN/m2) and 70 psf (3.35 kN/m2) are based on a ground snow load of 70 psf(3.35 kN/m2). For areas where the ground snow load is 40 psf (1.92 kN/m2), the solid wall lengths in this table are permitted to be reduced by multi-plying by the factor in Table 5.8. For ground snow loads between 40 (1.92) and 70 psf (3.35 kN/m2), use the value in Table 5.5A, B or C, or determinethe reduction factor by interpolation between the factors shown in Table 5.8 and 1.0. See Notes 4, 5 and 7.
7 Tabulated solid wall lengths are based on a default solid wall segment. To determine the required length of solid wall in each wall line, select a walltype, thickness, length of solid wall segment, and number, yield strength and arrangement of vertical bars at each end of the segment. Based on this,determine the adjustment factor from Table 5.4A or B and multiply it times the solid wall length from this table, including reductions, if any, fromNotes 4, 5 and 6.
8 For intermediate values of area, use the next higher value, or determine by interpolation. For lower values of SDS for a specific SDC determined inaccordance with Section 11.4.4 of ASCE 7, use the next higher value, or multiple tabular length by the ratio SDS /0.50, SDS /0.67, SDS /0.83, orSDS /1.00, whichever is appropriate.
O85573 1.qxd:FPO 85573 1 1/24/08 10:55 AM Page 5-17
Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
5-18
Table 5.5B. Unadjusted Length of Solid Wall, TL, Required in Each Exterior Endwall and Sidewall for Seismic ResistanceFirst Story of Two-Story1,4,5,7,8
SeismicDesign
Category
Groundsnowload6,
pg , – (psf)
Wallgroup3
Unadjusted length of solid wall, TL, required in each exterior wall line – (ft)
Area of building within exterior walls projected onto a horizontal plane – (sq ft)
200 300 400 600 800 1000 1500 2000 2500 3000 4000
CSDS = 0.50
< 40
1
2
3
4
≥ 40 – 70
1
2
3
4
D0
SDS = 0.67
< 40
1
2
3
4
≥ 40 – 70
1
2
3
4
D1
SDS = 0.83
< 40
1
2
3
4
≥ 40 – 70
1
2
3
4
D2
SDS = 1.00
< 40
1
2
3
4
≥ 40 – 70
1
2
3
4
26.17
31.13
37.08
43.28
28.64
33.60
39.55
45.75
28.05
33.37
39.75
46.40
30.70
36.02
42.40
49.04
34.75
41.34
49.24
57.48
38.03
44.62
52.52
60.76
41.87
49.81
59.33
69.25
45.82
53.76
63.28
73.20
22.61
27.05
32.38
37.93
24.61
29.05
34.38
39.94
24.23
29.00
34.71
40.67
26.38
31.14
36.86
42.81
30.02
35.92
43.00
50.38
32.68
38.58
45.66
53.04
36.17
43.28
51.81
60.70
39.37
46.48
55.01
63.90
35.97
42.23
49.73
57.55
39.84
46.09
53.60
61.41
38.56
45.27
53.32
61.70
42.70
49.41
57.46
65.84
47.77
56.08
66.05
76.43
52.90
61.21
71.18
81.56
57.56
67.57
79.58
92.09
63.74
73.74
85.75
98.26
29.56
34.99
41.50
48.28
32.50
37.92
44.43
51.22
31.69
37.51
44.49
51.76
34.84
40.65
47.63
54.90
39.26
46.46
55.11
64.12
43.16
50.36
59.01
68.02
47.30
55.98
66.40
77.25
51.99
60.68
71.09
81.95
12.76
15.59
19.00
22.54
13.62
16.45
19.85
23.40
13.68
16.72
20.36
24.16
14.60
17.64
21.28
25.08
16.94
20.71
25.23
29.93
18.08
21.85
26.37
31.07
20.41
24.95
30.39
36.07
21.79
26.32
31.77
37.44
10.76
13.22
16.18
19.26
11.42
13.88
16.84
19.92
11.53
14.17
17.34
20.65
12.24
14.88
18.05
21.36
14.28
17.56
21.49
25.58
15.16
18.44
22.37
26.46
17.21
21.15
25.89
30.82
18.27
22.21
26.95
31.88
18.80
22.65
27.28
32.10
20.33
24.18
28.81
33.63
20.15
24.29
29.25
34.42
21.79
25.93
30.89
36.06
24.96
30.09
36.23
42.63
26.99
32.12
38.26
44.67
30.08
36.25
43.65
51.37
32.52
38.69
46.10
53.81
14.61
17.77
21.56
25.51
15.66
18.82
22.61
26.57
15.66
19.05
23.11
27.35
16.78
20.17
24.24
28.48
19.40
23.59
28.63
33.88
20.79
24.99
30.03
35.28
23.37
28.43
34.50
40.82
25.05
30.11
36.18
42.51
7.24
9.01
11.12
13.33
7.60
9.37
11.48
13.69
7.76
9.65
11.92
14.28
8.15
10.04
12.31
14.67
9.62
11.96
14.77
17.70
10.10
12.44
15.25
18.17
11.59
14.41
17.79
21.32
12.16
14.99
18.37
21.90
5.80
7.25
9.00
10.81
6.06
7.51
9.25
11.07
6.22
7.78
9.64
11.59
6.49
8.05
9.92
11.86
7.70
9.63
11.95
14.36
8.04
9.97
12.29
14.70
9.28
11.60
14.39
17.30
9.69
12.01
14.80
17.71
8.51
10.54
12.97
15.50
8.98
11.00
13.43
15.96
9.13
11.30
13.90
16.62
9.62
11.79
14.40
17.11
11.30
13.99
17.22
20.58
11.92
14.61
17.84
21.20
13.62
16.86
20.75
24.80
14.36
17.60
21.49
25.54
For SI: 1 ft. = 0.3048 m; 1 sq. ft. = 0.0929 m2; 1 psf = 0.0479 kN/m2
For notes see page 5-17.
O85573 1.qxd:FPO 85573 1 1/24/08 10:55 AM Page 5-18
5-19
Chapter 5 – Solid Walls for Resistance to Lateral Forces
Table 5.5C. Unadjusted Length of Solid Wall, TL, Required in Each Exterior Endwall and Sidewall for Seismic ResistanceFirst Story of Two-Story with Second Story Exterior Walls of Light-Framed Construction1,4,5,7,8
SeismicDesign
Category
Groundsnowload6,
pg , – psf
Wallgroup3
Unadjusted length of solid wall, TL, required in each exterior wall line – (ft)
Area of building within exterior walls projected onto a horizontal plane – (sq ft)
200 300 400 600 800 1000 1500 2000 2500 3000 4000
CSDS = 0.50
< 40
1
2
3
4
≥ 40 – 70
1
2
3
4
D0
SDS = 0.67
< 40
1
2
3
4
≥ 40 – 70
1
2
3
4
D1
SDS = 0.83
< 40
1
2
3
4
≥ 40 – 70
1
2
3
4
D2
SDS = 1.00
< 40
1
2
3
4
≥ 40 – 70
1
2
3
4
16.82
18.32
20.11
21.98
19.29
20.79
22.58
24.45
18.03
19.64
21.56
23.57
20.68
22.28
24.21
26.22
22.34
24.33
26.71
29.20
25.62
27.61
29.99
32.48
26.91
29.31
32.18
35.18
30.87
33.26
36.13
39.13
14.23
15.57
17.18
18.86
16.23
17.57
19.18
20.86
15.25
16.69
18.42
20.21
17.40
18.84
20.56
22.36
18.90
20.68
22.82
25.04
21.56
23.34
25.47
27.70
22.77
24.91
27.49
30.17
25.97
28.12
30.69
33.37
24.18
26.07
28.34
30.69
28.04
29.93
32.20
34.56
25.92
27.95
30.38
32.90
30.06
32.09
34.51
37.04
32.11
34.62
37.63
40.76
37.24
39.75
42.76
45.89
38.69
41.71
45.34
49.11
44.87
47.89
51.51
55.29
19.33
20.97
22.93
24.98
22.27
23.90
25.87
27.92
20.72
22.48
24.59
26.78
23.87
25.63
27.73
29.93
25.67
27.85
30.46
33.18
29.57
31.75
34.36
37.07
30.93
33.55
36.70
39.97
35.63
38.25
41.39
44.67
7.41
8.27
9.30
10.37
8.27
9.13
10.15
11.22
7.95
8.86
9.96
11.11
8.87
9.78
10.88
12.03
9.84
10.98
12.34
13.76
10.98
12.12
13.48
14.90
11.86
13.23
14.87
16.58
13.23
14.60
16.25
17.96
6.11
6.85
7.75
8.68
6.77
7.52
8.41
9.34
6.55
7.35
8.30
9.30
7.26
8.06
9.01
10.01
8.11
9.10
10.29
11.52
8.99
9.98
11.17
12.40
9.78
10.97
12.39
13.88
10.84
12.03
13.45
14.94
11.53
12.69
14.09
15.54
13.06
14.22
15.62
17.07
12.36
13.60
15.10
16.66
14.00
15.24
16.74
18.30
15.31
16.85
18.71
20.64
17.34
18.88
20.74
22.67
18.44
20.30
22.54
24.87
20.89
22.75
24.99
27.31
8.64
9.60
10.74
11.94
9.70
10.65
11.80
12.99
9.27
10.29
11.52
12.80
10.39
11.42
12.64
13.92
11.48
12.75
14.27
15.85
12.88
14.14
15.66
17.25
13.83
15.36
17.19
19.10
15.51
17.04
18.87
20.78
3.92
4.45
5.09
5.75
4.28
4.81
5.45
6.11
4.20
4.77
5.46
6.17
4.59
5.16
5.84
6.55
5.20
5.91
6.76
7.64
5.68
6.39
7.24
8.12
6.27
7.12
8.14
9.21
6.85
7.70
8.72
9.78
3.06
3.50
4.03
4.57
3.32
3.76
4.28
4.83
3.28
3.75
4.32
4.90
3.56
4.03
4.59
5.18
4.07
4.65
5.35
6.08
4.41
4.99
5.69
6.42
4.90
5.60
6.44
7.32
5.31
6.01
6.85
7.73
4.69
5.31
6.04
6.80
5.16
5.77
6.50
7.27
5.03
5.69
6.47
7.29
5.53
6.18
6.97
7.79
6.23
7.05
8.02
9.03
6.85
7.66
8.63
9.65
7.51
8.49
9.66
10.89
8.25
9.23
10.40
11.63
For SI: 1 ft. = 0.3048 m; 1 sq. ft. = 0.0929 m2; 1 psf = 0.0479 kN/m2
For notes see page 5-17.
O85573 1.qxd:FPO 85573 1 1/24/08 10:55 AM Page 5-19
Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
5-20
Table 5.6A. Reduction Factor, R5.6 , for Floor-to-Ceiling Wall Heights of Less than 10 FeetSecond Story Exterior Walls of Concrete Construction1
Floor toceiling height,
(ft)2
Wallgroup3
Reduction factor, R5.6 , for floor-to-ceiling wall heights of less than 10 feet
Area of building within exterior walls projected onto a horizontal plane – (sq ft)
200 300 400 600 800 1000 1500 2000 2500 3000 4000
One story or top story of two-story
8' top story
1
2
3
4
9' top story
1
2
3
4
First story of two-story
8' top story and8' bottom story
1
2
3
4
8' top story and9' bottom story
1
2
3
4
8' top story and10' bottom story
1
2
3
4
9' top story and9' bottom story
1
2
3
4
9' top story and10' bottom story
1
2
3
4
0.92
0.90
0.89
0.88
0.96
0.95
0.95
0.94
0.91
0.90
0.89
0.88
0.95
0.95
0.94
0.94
0.93
0.91
0.90
0.89
0.96
0.96
0.95
0.95
0.92
0.91
0.90
0.89
0.96
0.95
0.95
0.94
0.89
0.88
0.87
0.86
0.94
0.94
0.93
0.93
0.88
0.87
0.86
0.85
0.94
0.94
0.93
0.93
0.90
0.89
0.88
0.87
0.95
0.95
0.94
0.94
0.89
0.88
0.87
0.86
0.95
0.94
0.94
0.93
0.87
0.86
0.85
0.84
0.93
0.93
0.92
0.92
0.86
0.85
0.84
0.84
0.93
0.93
0.92
0.92
0.87
0.86
0.85
0.85
0.94
0.93
0.93
0.92
0.89
0.88
0.87
0.86
0.91
0.90
0.89
0.89
0.93
0.92
0.91
0.91
0.95
0.94
0.94
0.93
0.96
0.96
0.96
0.95
0.89
0.88
0.87
0.86
0.91
0.90
0.89
0.88
0.92
0.92
0.91
0.91
0.94
0.94
0.93
0.93
0.96
0.96
0.96
0.95
0.90
0.89
0.88
0.87
0.92
0.91
0.90
0.89
0.93
0.93
0.92
0.91
0.95
0.94
0.94
0.94
0.97
0.96
0.96
0.96
0.89
0.88
0.87
0.87
0.91
0.90
0.90
0.89
0.93
0.92
0.92
0.91
0.95
0.94
0.94
0.93
0.96
0.96
0.96
0.96
0.87
0.86
0.85
0.85
0.89
0.88
0.88
0.87
0.91
0.91
0.90
0.90
0.93
0.93
0.93
0.92
0.96
0.95
0.95
0.95
0.86
0.86
0.85
0.84
0.89
0.88
0.87
0.87
0.91
0.90
0.90
0.90
0.93
0.93
0.92
0.92
0.95
0.95
0.95
0.95
0.88
0.87
0.86
0.86
0.90
0.89
0.89
0.88
0.92
0.91
0.91
0.90
0.94
0.94
0.93
0.93
0.96
0.96
0.95
0.95
0.87
0.86
0.86
0.85
0.89
0.89
0.88
0.88
0.92
0.91
0.90
0.90
0.94
0.93
0.93
0.93
0.96
0.95
0.95
0.95
0.85
0.85
0.84
0.84
0.88
0.87
0.87
0.87
0.90
0.90
0.89
0.89
0.93
0.92
0.92
0.92
0.95
0.95
0.95
0.95
0.85
0.84
0.84
0.84
0.87
0.87
0.87
0.86
0.90
0.90
0.89
0.89
0.92
0.92
0.92
0.92
0.95
0.95
0.95
0.95
0.86
0.85
0.84
0.84
0.88
0.88
0.87
0.87
0.91
0.90
0.90
0.89
0.93
0.93
0.92
0.92
0.95
0.95
0.95
0.95
For SI: 1 ft. = 0.3048 m; 1 sq. ft. = 0.0929 m2
1 Tables 5.5A, B and C are based on floor-to-ceiling wall heights of 10 feet (3.0 m). Where heights are less than 10 feet (3.0 m), the solid wall lengthsin Tables 5.5A, B and C are permitted to be reduced by multiplying by the appropriate factor from this table.
2 For intermediate floor to ceiling wall heights and building areas, use the next higher factor or determine by interpolation.3 Wall group 1 includes 6-inch (152 mm) waffle-grid and 6-inch (152 mm) screen-grid. Wall group 2 includes 6-inch (152 mm) flat and 8-inch (203
mm) waffle-grid. Wall group 3 is 8-inch (203 mm) flat, and wall group 4 is 10-inch (254 mm) flat. See Table 2.1 for minimum dimensions. See Section5.3.2 for minimum thicknesses.
O85573 1.qxd:FPO 85573 1 1/24/08 10:55 AM Page 5-20
5-21
Chapter 5 – Solid Walls for Resistance to Lateral Forces
Table 5.6B. Reduction Factor, R5.6, for Floor-to-Ceiling Wall Heights of Less than 10 Feet Second Story Exterior Walls of Light-Framed Construction1
Floor toceiling height,
(ft)2
Wallgroup3
Reduction factor, R5.6 , for floor-to-ceiling wall heights of less than 10 feet
Area of building within exterior walls projected onto a horizontal plane – (sq ft)
200 300 400 600 800 1000 1500 2000 2500 3000 4000
First story of two-story
8' top story and8' bottom story
1
2
3
4
8' top story and9' bottom story
1
2
3
4
8' top story and10' bottom story
1
2
3
4
9' top story and9' bottom story
1
2
3
4
9' top story and10' bottom story
1
2
3
4
0.92
0.91
0.90
0.90
0.95
0.95
0.94
0.94
0.98
0.98
0.98
0.98
0.96
0.96
0.95
0.95
0.99
0.99
0.99
0.99
0.92
0.91
0.90
0.89
0.95
0.94
0.94
0.94
0.97
0.98
0.98
0.98
0.96
0.95
0.95
0.95
0.99
0.99
0.99
0.99
0.93
0.92
0.91
0.91
0.96
0.95
0.95
0.94
0.98
0.98
0.98
0.98
0.97
0.96
0.96
0.95
0.99
0.99
0.99
0.99
0.93
0.92
0.91
0.90
0.95
0.95
0.94
0.94
0.98
0.98
0.98
0.98
0.96
0.96
0.95
0.95
0.99
0.99
0.99
0.99
0.90
0.89
0.88
0.87
0.93
0.93
0.93
0.92
0.97
0.97
0.97
0.98
0.95
0.94
0.94
0.94
0.98
0.99
0.99
0.99
0.89
0.88
0.87
0.86
0.93
0.92
0.92
0.92
0.97
0.97
0.97
0.97
0.94
0.94
0.94
0.93
0.98
0.98
0.99
0.99
0.91
0.90
0.89
0.88
0.94
0.94
0.93
0.93
0.97
0.97
0.98
0.98
0.95
0.95
0.95
0.94
0.99
0.99
0.99
0.99
0.90
0.89
0.88
0.88
0.93
0.93
0.93
0.93
0.97
0.97
0.97
0.98
0.95
0.95
0.94
0.94
0.98
0.99
0.99
0.99
0.87
0.87
0.86
0.85
0.92
0.92
0.91
0.91
0.96
0.97
0.97
0.97
0.94
0.93
0.93
0.93
0.98
0.98
0.98
0.99
0.87
0.86
0.85
0.85
0.91
0.91
0.91
0.91
0.96
0.96
0.97
0.97
0.93
0.93
0.93
0.92
0.98
0.98
0.98
0.99
0.88
0.87
0.86
0.86
0.92
0.92
0.92
0.92
0.96
0.97
0.97
0.97
0.94
0.94
0.93
0.93
0.98
0.98
0.99
0.99
For SI: 1 ft. = 0.3048 m; 1 sq. ft. = 0.0929 m2
1 Tables 5.5A, B and C are based on floor-to-ceiling wall heights of 10 feet (3.0 m). Where heights are less than 10 feet (3.0 m), the solid wall lengthsin Tables 5.5A, B and C are permitted to be reduced by multiplying by the appropriate factor from this table.
2 For intermediate wall heights and building areas, use the next higher factor or determine by interpolation.3 Wall group 1 includes 6-inch (152 mm) waffle-grid and 6-inch (152 mm) screen-grid. Wall group 2 includes 6-inch (152 mm) flat and 8-inch (203
mm) waffle-grid. Wall group 3 is 8-inch (203 mm) flat, and wall group 4 is 10-inch (254 mm) flat. See Table 2.1 for minimum dimensions. See Section5.3.2 for minimum thicknesses.
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Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
5-22
Table 5.7. Reduction Factor, R5.7, for Exterior Wall Covering Weighing 3 psf or Less1
Wallgroup2
Reduction factor, R5.7, for light-weight exterior wall covering weighing 3 psf or less
Area of building within exterior walls projected onto a horizontal plane – (sq ft)
200 300 400 600 800 1000 1500 2000 2500 3000 4000
One story or top story of two-story
1
2
3
4
First story of two-story
1
2
3
4
First story of two-story with second story exterior walls of light-framed construction
1
2
3
4
0.93
0.94
0.95
0.95
0.93
0.94
0.94
0.95
0.93
0.94
0.95
0.95
0.93
0.94
0.95
0.95
0.92
0.93
0.94
0.95
0.92
0.93
0.94
0.95
0.93
0.94
0.94
0.95
0.92
0.93
0.94
0.95
0.91
0.93
0.94
0.95
0.91
0.93
0.94
0.95
0.92
0.93
0.94
0.95
0.92
0.93
0.94
0.95
0.92
0.93
0.94
0.95
0.93
0.94
0.95
0.95
0.92
0.93
0.94
0.95
0.91
0.93
0.94
0.95
0.91
0.92
0.94
0.95
0.92
0.93
0.94
0.95
0.91
0.93
0.94
0.95
0.90
0.92
0.94
0.95
0.90
0.92
0.93
0.95
0.90
0.92
0.94
0.95
0.89
0.90
0.91
0.91
0.89
0.90
0.90
0.91
0.90
0.91
0.92
0.92
0.90
0.90
0.91
0.92
0.86
0.88
0.89
0.90
0.86
0.87
0.89
0.90
0.88
0.89
0.90
0.91
0.87
0.88
0.89
0.90
0.84
0.86
0.88
0.89
0.83
0.85
0.87
0.89
0.85
0.86
0.88
0.89
For SI: 1 sq. ft. = 0.0929 m2; 1 psf = 0.0479 kN/m2
1 Tables 5.5A, B and C are based on an exterior wall covering having an installed weight of 11 psf (0.53 kN/m2) (e.g., 7⁄8-inch (22 mm) cement stucco).Where the exterior wall covering has an installed weight of 3 psf (0.14 kN/m2) or less (e.g., 5⁄16-inch (8 mm) fiber-cement siding, vinyl siding), thesolid wall lengths in Tables 5.5A, B and C are permitted to be reduced by multiplying by the factor in this table. For intermediate building areas, usethe next higher value or determine factor by interpolation. For exterior wall coverings having an installed weight of greater than 3 psf (0.14 kN/m2)and less than 11 psf (0.53 kN/m2), use the solid wall length in Table 5.5A, B or C, or determine the reduction factor by interpolation between thefactors shown in this table and 1.0.
2 Wall group 1 includes 6-inch (152 mm) waffle-grid and 6-inch (152 mm) screen-grid. Wall group 2 includes 6-inch (152 mm) flat and 8-inch (203mm) waffle-grid. Wall group 3 is 8-inch (203 mm) flat, and wall group 4 is 10-inch (254 mm) flat. See Table 2.1 for minimum dimensions. See Section5.3.2 for minimum thicknesses.
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5-23
Chapter 5 – Solid Walls for Resistance to Lateral Forces
Table 5.8. Reduction Factor, R5.8 , for Ground Snow Load Equal to 40 psf 1
Wallgroup2
Reduction factor, R5.8 , for ground snow load of 40 psf
Area of building within exterior walls projected onto a horizontal plane – sq ft
200 300 400 600 800 1000 1500 2000 2500 3000 4000
One story or top story of two-story
1
2
3
4
First story of two-story
1
2
3
4
First story of two-story with second story exterior walls of light-framed construction
1
2
3
4
0.92
0.92
0.93
0.94
0.92
0.93
0.94
0.94
0.91
0.92
0.93
0.93
0.91
0.92
0.93
0.94
0.93
0.94
0.95
0.96
0.94
0.95
0.95
0.96
0.92
0.93
0.94
0.95
0.93
0.94
0.95
0.95
0.95
0.95
0.96
0.97
0.95
0.96
0.97
0.97
0.94
0.95
0.96
0.96
0.96
0.97
0.97
0.98
0.97
0.97
0.98
0.98
0.96
0.96
0.97
0.97
0.96
0.97
0.97
0.98
0.97
0.98
0.98
0.98
0.98
0.98
0.98
0.99
0.97
0.97
0.98
0.98
0.97
0.98
0.98
0.98
0.98
0.98
0.99
0.99
0.98
0.99
0.99
0.99
0.98
0.98
0.99
0.99
0.95
0.95
0.95
0.96
0.95
0.95
0.96
0.96
0.94
0.94
0.95
0.95
0.94
0.95
0.95
0.95
0.96
0.96
0.96
0.97
0.96
0.96
0.97
0.97
0.95
0.95
0.96
0.96
0.95
0.96
0.96
0.97
0.96
0.97
0.97
0.97
0.97
0.97
0.97
0.98
0.96
0.97
0.97
0.97
For SI: 1 psf = 0.0479 kN/m2; 1 sq. ft. = 0.0929 m2
1 ASCE 7 requires that a portion of the roof snow load be considered as a part of the seismic weight of the building where the ground snow load isapproximately 40 psf (1.92 kN/m2) or greater. Tables 5.5A, B and C considers two conditions: one where the ground snow load is less than 40 psf(1.92 kN/m2), and a second where the ground snow load is 70 psf (3.35 kN/m2). For areas where the ground snow load is 40 psf (1.92 kN/m2), thesolid wall lengths in Tables 5.5A, B and C are permitted to be reduced by multiplying by the factor in this table. For intermediate building areas, usethe next higher value or determine factor by interpolation. For ground snow loads between 40 (1.92) and 70 psf (3.35 kN/m2), use the value in Table5.5A, B or C, or determine the reduction factor by interpolation between the factors shown in this table and 1.0.
2 Wall group 1 includes 6-inch (152 mm) waffle-grid and 6-inch (152 mm) screen-grid. Wall group 2 includes 6-inch (152 mm) flat and 8-inch (203 mm)waffle-grid. Wall group 3 is 8-inch (203 mm) flat, and wall group 4 is 10-inch (254 mm) flat. See Table 2.1 for minimum dimensions. See Section 5.3.2for minimum thicknesses.
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Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
5-24
∗ For minimum cover see Section 2.5.1
1" Min. clear spacing typical
∗
3" Max. typical*
2" Typical
DetailNo. Notes
Nom. wallthickness, in.
Reinforcement layout at ends ofsolid wall segments
2
1
3
4
5
6
7
8
4
4
68
10
6
8
8
10
10
1. See Tables 5.4A and B for use of details.
2. Minimum length of solid wall segment, and size and grade of reinforcement in each end of each solid wall segment shall be deter-mined from Table 5.4A or B.
3. For minimum cover require-ments, see Section 2.5.1.
4. For details 3 – 8 where two or more bars are in the same row parallel to the end of the segment, place bars so that corner bars are as close to the sides of the wall segments as min-imum cover requirements of Section 2.5.1 will permit.
5. For waffle- and screen-grid walls, each end of each solid wall segment shall have rectangular flanges. In the through-the-wall dimension, the flange shall not be less than 5.5 inches for 6-inch nominal waffle- and screen-grid forms, and not less than 7.5 inches for 8-inch nominal waffle-grid forms. In the in-plane dimension, flanges shall be long enough to accommo-date the vertical reinforce-ment required by the layout detail selected and provide the cover required by Section 2.5.1. If necessary to achieve the required dimensions, form material shall be removed or flat wall forms are permitted to be used. See Table 5.4B, Note 9.
For SI: 1 in. = 25.4 mmFigure 5.1. Reinforcement layout details at ends of solid wall segments for use with Tables 5.4A and B.
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5-25
Chapter 5 – Solid Walls for Resistance to Lateral Forces
A B C
D E LSidewall
WEndwall
L
Sidewall
WEndwall
Wind or seismicperpendicularto ridge
One-story or top story of two-story(Tables 5.1A and 5.5A)See Sections 5.1.1 and 5.1.2
First story of two-story(Tables 5.1B, 5.5B, and 5.5C)See Sections 5.1.1 and 5.1.2
One-story or top story of two-story(Tables 5.1C, and 5.5A)See Sections 5.1.1 and 5.1.2
First story of two-story(Tables 5.1C, 5.5B, and 5.5C)See Sections 5.1.1 and 5.1.2
F
E
D
C
B
A
Wind or seismicparallel to ridge
Note: Each solid wall segment (A, B, C, D, E, and F) shall comply with the minimum solid wall segment length in order to be applicable to the minimum solid wall length. See Section 5.2. See Section 1.2.2 for limitation of location of solid wall segments in SDC C, D0, D1, or D2.
Figure 5.2. Variables for use with equations in Sections 5.1.1 and 5.1.2.
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Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
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6-1
Chapter 6Requirements for Connections and Diaphragms
6.1 CONNECTIONS – GENERALConcrete walls shall be connected to footings, floors, ceilingsand roofs in accordance with this chapter. Requirements forinstallation of masonry veneer, stucco and other finishes onthe exterior of concrete walls and other construction detailsnot covered in this chapter shall comply with the require -ments of the applicable building code, or withmanufacturers’ recommendations where there is no code.
6.2 FOUNDATION WALL-TO-FOOTINGCONNECTIONFor buildings assigned to Seismic Design Category A, B, or Cand located where the wind velocity pressure in accordancewith Table 5.1A is less than or equal to 40 psf (1.95 kN/m2),No. 4 Grade 40 (280 MPa) vertical dowels at a maximumspacing of 32 inches (813 mm) on center, or No. 5 verticaldowels at a maximum spacing of 48 inches (1219 mm) oncenter shall be installed across the construction joint betweenthe foundation wall and the footing in accordance withFigure 6.1.
EXCEPTIONS: Vertical dowels are not required acrossthe construction joint between the foundation wall andthe footing where one of the following exists:
1. The unbalanced backfill height does not exceed 4 feet(1.2 m).
2. The interior floor slab-on-ground is installed in accor-dance with Figure 3.3 before backfilling.
3. Temporary bracing at the bottom of the foundationwall is erected before backfilling and remains in placeduring construction until an interior floor slab-on-ground is installed in accordance with Figure 3.3 orthe wall is backfilled on both sides (i.e., stem wall).
4. The foundation wall’s vertical reinforcement ispermitted to serve in lieu the dowels, provided the size
and spacing complies with the above requirementsand embedment in the footing complies with Figure 6.1.
For all buildings, the vertical wall reinforcement at each endof each solid wall segment (see Section 5.2) shall bedeveloped below the bottom of the adjacent wall opening(see Figure 6.2) by one of the following methods:
1) Where the wall height below the bottom of the adjacentopening is equal to or greater than 22 inches (559 mm)for No. 4 or 28 inches (711 mm) for No. 5 vertical wallreinforcement, reinforcement around openings in accor-dance with Section 7.1 shall be sufficient, or
2) Where the wall height below the bottom of the adjacentopening is less than required by Item 1 above, the verticalwall reinforcement adjacent to the opening shall extendinto the footing far enough to develop the bar in tensionin accordance with Section 2.5.4 and Figure 2.5, or shallbe lap-spliced with a dowel that is embedded in thefooting far enough to develop the dowel-bar in tension.
For buildings located where the wind velocity pressure inaccordance with Table 5.1A is greater than 40 psf (1.95 kN/m2),No. 5 vertical dowels at a maximum spacing of 18 inches(457 mm) on center or No. 4 vertical dowels at a maximumspacing of 12 inches (305 mm) on center shall be provided.The dowels shall extend into the footing and the foundationwall in accordance with Figure 6.1. In lieu of the dowels,vertical reinforcement required in the foundation wall byChapter 3 is permitted to extend into the footing 8 inches(203 mm), provided the area of steel per foot (305 mm) ofwall is not less than 0.20 square inches (129 mm2).
For buildings assigned to Seismic Design Category D0, D1 orD2, the vertical wall reinforcement required by Sections 3.2.4and 4.1 shall extend into the footing a minimum of 8 inches(203 mm), or lap-spliced with dowels that are embedded inthe footing in accordance with Figure 6.1.
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2. For floor systems of cold-formed steel construction, theprovisions of Section 6.3 and the prescriptive details ofFigures 6.7 through 6.10, where permitted by the figuretables. Portions of connections of cold-formed steelframed floor systems not noted in the figures shall be inaccordance with AISI/S230.
3. Proprietary connectors selected to resist loads and loadcombinations in accordance with Appendix A (ASD) orAppendix B (LRFD).
4. An engineered design using loads and load combinationsin accordance with Appendix A (ASD) or Appendix B(LRFD).
5. An engineered design using loads and material designprovisions in accordance with the applicable buildingcode. In the absence of a building code, design shall bein accordance with ASCE 7, ACI 318, and AF&PA/NDS forwood frame construction or AISI/S100 for cold-formedsteel frame construction.
6.5 CONNECTIONS BETWEENCONCRETE WALLS AND LIGHT-FRAMED CEILING AND ROOFSYSTEMSConnections between concrete walls and light-framed ceilingand roof systems shall be in accordance with one of thefollowing:
1. For ceiling and roof systems of wood frame construction,the provisions of Section 6.3 and the prescriptive detailsof Figures 6.11 and 6.12, where permitted by the figuretables. Portions of connections of wood framed ceilingand roof systems not noted in the figures shall be inaccordance with AF&PA/WFCM.
2. For ceiling and roof systems of cold-formed steel con -struction, the provisions of Section 6.3 and the prescrip-tive details of Figures 6.13 and 6.14, where permitted bythe figure tables. Portions of connections of cold-formedsteel framed ceiling and roof systems not noted in thefigures shall be in accordance with AISI/S230.
3. Proprietary connectors selected to resist loads and loadcombinations in accordance with Appendix A (ASD) orAppendix B (LRFD).
4. An engineered design using loads and load combinationsin accordance with Appendix A (ASD) or Appendix B(LRFD).
5. An engineered design using loads and material designprovisions in accordance with the applicable buildingcode. In the absence of a building code, design shall bein accordance with ASCE 7, ACI 318, and AF&PA/NDS for
6.3 CONNECTIONS BETWEENCONCRETE WALLS AND LIGHT-FRAMED FLOOR, CEILING AND ROOFSYSTEMSConnections between concrete walls and light-framed floor,ceiling and roof systems utilizing the prescriptive details ofFigures 6.3 through 6.14 shall comply with this section andSection 6.4 or 6.5.
6.3.1 Anchor BoltsAnchor bolts used to connect light-framed floor, ceiling androof systems to concrete walls in accordance with Figures 6.3through 6.14 shall have heads, or shall be rods with threadson both ends with a hex or square nut on the end embeddedin the concrete. Bolts and threaded rods shall comply withSection 2.3.2. Anchor bolts with J- or L-hooks shall not beused where the connection details in these figures are used.
6.3.2 Removal of Stay-in-Place Form Material atBoltsHoles in stay-in-place forms for installing bolts for attachingface-mounted wood ledger boards to the wall shall be aminimum of 4 inches (102 mm) in diameter for forms notgreater than 11⁄2 inches (38 mm) in thickness, and increasedone inch (25 mm) in diameter for each 1⁄2-inch (13 mm)increase in form thickness. Holes in stay-in-place forms forinstalling bolts for attaching face-mounted cold-formed steeltracks to the wall shall be a minimum of 4 inches (102 mm)square. The wood ledger board or steel track shall be indirect contact with the concrete at each bolt location.
EXCEPTION: A vapor retarder or other material lessthan or equal to 1⁄16-inch (1.6 mm) in thickness ispermitted to be installed between the wood ledger orcold-formed steel track and the concrete.
6.4 CONNECTIONS BETWEENCONCRETE WALLS AND LIGHT-FRAMED FLOOR SYSTEMSConnections between concrete walls and light-framed floorsystems shall be in accordance with one of the following:
1. For floor systems of wood frame construction, the provi-sions of Section 6.3 and the prescriptive details of Figures6.3 through 6.6, where permitted by the figure tables.Portions of connections of wood framed floor systemsnot noted in the figures shall be in accordance withAF&PA/WFCM.
6-2
Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
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Chapter 6 – Requirements for Connections and Diaphragms
6.6.2 Roof and Ceiling Diaphragm ConstructionRoof and ceiling diaphragms shall have wood structuralpanel sheathing having a thickness of not less than 7⁄16 inch(11 mm). Sheathing shall be fastened with nails to contin -uous wood framing members and to blocking, whereblocking is required. Nails shall be 8d common for 7⁄16 inch(11 mm) sheathing and 10d common for 15/32 inch (12 mm)and thicker sheathing. Sheathing shall be fastened with No.8 screws to continuous cold-formed steel framing membersand to blocking, where blocking is required. For buildingsassigned to Seismic Design Category A or B, and detachedone- and two-family dwellings assigned to Seismic DesignCategory C, the spacing of fasteners in sheathing shall notexceed the dimensions in Table 6.3 or Table 6.4 for winddesign for wood and cold-formed steel framing members,respectively. For multiple dwellings assigned to SeismicDesign Category C, and all buildings assigned to SeismicDesign Category D0, D1 or D2, the spacing of fasteners insheathing shall not exceed the more stringent dimensions inTable 6.3 or Table 6.4 for wind and seismic design for woodand cold-formed steel framing members, respectively.Blocked diaphragms complying with Section 6.6.3 shall beprovided where required by Table 6.3 or Table 6.4.
6.6.3 Blocked DiaphragmsWhere Table 6.1 or Table 6.3 requires blocked diaphragmsin wood framed construction, blocking shall be minimum2-inch (51 mm) nominal framing lumber located under allsheathing panel edges perpendicular to the framing members.Blocking shall be the same depth as the framing members.Blocking shall be attached to the framing members with aminimum of two 8d common nails at each end.
Where Table 6.2 or Table 6.4 requires blocked diaphragmsin cold-formed steel framed construction, blocking shall beminimum 43 mil (1.1 mm) C-section or track located underall sheathing panel edges perpendicular to the framingmembers. Blocking shall be attached to the framing memberswith a minimum of two No. 8 screws at each end.
6.6.4 Diaphragm Continuous TiesIn multiple dwellings assigned to Seismic Design Category Cand all buildings assigned to Seismic Design Category D0, D1
or D2, continuous ties shall be provided across the entirediaphragm width at each tension tie. In the direction perpen-dicular to main framing members, the continuous tie shall beminimum 54 mil (1.4 mm) thick Grade 50 steel straps whichshall extend across the entire diaphragm width at eachtension tie and be a continuation of the tension tie. Theminimum width of the strap shall be determined from Figure
wood frame construction or AISI/S100 for cold-formedsteel frame construction.
6.6 FLOOR, ROOF AND CEILINGDIAPHRAGM CONSTRUCTIONFloors and roofs in all buildings shall be designed and con -structed as diaphragms. Where gable-end walls occur, ceilingsshall also be designed and constructed as diaphragms. Thedesign and construction of floors, roofs and ceilings of woodframing or cold-formed steel framing serving as diaphragmsshall comply with the applicable building code. Where there isno code, the design and construction of diaphragms withwood framing members shall comply with AF&PA/WFCM, anddiaphragms with cold-formed steel framing members shallcomply with AISI/S230. For multiple dwellings assigned toSeismic Design Category C, and all buildings assigned toSeismic Design Category D0, D1 or D2, the mini mum thicknessof sheathing, requirements for blocked diaphragms, andfastening of sheathing to the framing members and toblocking, where blocking is required, shall comply with themost stringent requirements of the applicable building code, ifany, AF&PA/WFCM or AISI/S230, and this section. For multipledwellings assigned to Seismic Design Category C, and allbuildings assigned to Seismic Design Category D0, D1 or D2,diaphragm continuous ties complying with Section 6.6.4 shallbe provided in all cases.
6.6.1 Floor diaphragm constructionFloor diaphragms shall have wood structural panel sheathinghaving a thickness of not less than 19⁄32 inch (15 mm) forwood framed floors, and not less than 15⁄32 inch (12 mm) forcold-formed steel framed floors. Sheathing shall be fastenedwith 10d common nails to continuous wood framing mem -bers and to blocking, where blocking is required. Sheathingshall be fastened with No. 8 screws to continuous cold-formed steel framing members and to blocking, whereblock ing is required. For buildings assigned to Seismic DesignCategory A or B, and detached one- and two-family dwellingsassigned to Seismic Design Category C, the spacing offasteners in sheathing shall not exceed the dimensions inTable 6.1 or Table 6.2 for wind design for wood and cold-formed steel framing members, respectively. For multipledwellings assigned to Seismic Design Category C, and allbuildings assigned to Seismic Design Category D0, D1 or D2,the spacing of fasteners in sheathing shall not exceed themore stringent dimensions in Table 6.1 or Table 6.2 for windand seismic design for wood and cold-formed steel framingmembers, respectively. Blocked diaphragms complying withSection 6.6.3 shall be provided where required by Table 6.1or Table 6.2.
6-3
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Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
6-4
6.4, 6.6, 6.8, 6.10, 6.12 or 6.14, whichever is applicable.The steel strap shall be located on top of the wood structuralpanel sheathing or between the sheathing and wood orcold-formed steel framing members.
In diaphragms with wood framing members, the steel strapcontinuous tie shall be fastened through the sheathing toframing or blocking with 10d common nails spaced not toexceed the dimension in Table 6.1 for floor diaphragms, andTable 6.3 for roof and ceiling diaphragms. Blocking forattaching the continuous tie strap need not be full depth;however, the minimum dimension of the blocking shall be2-inch (51 mm) nominal. The blocking shall be attached tothe framing members with a minimum of two 8d commonnails at each end.
In diaphragms with cold-formed steel framing members,the steel strap continuous tie shall be fastened through thesheathing to framing or blocking with No. 8 screws spacednot to exceed the dimension in Table 6.2 for floor diaphragms,and Table 6.4 for roof and ceiling diaphragms. Blocking forattaching the continuous tie strap need not be full depth;however, as a minimum it shall be 43 mil (1.1 mm) C-sectionor track. The blocking shall be attached to the framingmembers with a minimum of two No. 8 screws at each end.
Blocking in blocked diaphragms used for the support andattachment of sheathing panel edges that is also used forattaching continuous ties shall comply with Section 6.6.3.
Wind Design
BuildingAspectRatio
Maximum Nail Spacing in Sheathing in Blocked Diaphragms at Locations a/b3 – in.Basic Wind Speed (mph) and Exposure Category
85B 90B 100B 110B 120B 130B 140B 150B 166B 179B 192B85C 90C 100C 110C 120C 130C 140C 150C 163C
85D 90D 100D 110D 120D 130D 140D 150D1 – 1.33 UB UB UB UB UB UB UB 6/6 6/6 6/6 4/6
>1.33 – 1.67 UB UB UB UB UB UB 6/6 6/6 4/6 4/6 2.5/4>1.67 – 2 UB UB UB UB UB 6/6 6/6 4/6 4/6 2.5/4 2.5/4
Seismic Design
BuildingAspectRatio
Maximum Nail Spacing in Sheathing in Blocked Diaphragms at Locations a/b3 – in.Seismic Design Category
C D0 D1 D2
Wall Group4 Wall Group4 Wall Group4 Wall Group4
1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 41 – 1.33 UB UB UB UB UB UB UB 6/6 UB UB 6/6 6/6 UB 6/6 6/6 6/6
>1.33 – 1.67 UB UB UB UB UB UB 6/6 6/6 UB 6/6 6/6 6/6 6/6 6/6 4/6 4/6>1.67 – 2 UB UB UB 6/6 UB UB 6/6 6/6 6/6 6/6 6/6 4/6 6/6 6/6 4/6 2.5/4
For SI: 1 inch = 25.4 mm; 1 mph = 0.4470 m/s1 UB means unblocked diaphragm permitted2 In unblocked diaphragms, space nails a maximum of 6 inches (152 mm) on center at all supported panel edges, at tension ties, and at continuous tie
locations, where continuous ties are required by Section 6.6.4, and 12 inches (305 mm) on center in the field of the panel.3 In blocked diaphragms, maximum nail spacing in inches:
a. at diaphragm boundary edges and all continuous panel edges,b. at all other panel edges, at tension ties, and at continuous tie locations, where continuous ties are required by Section 6.6.4, andc. at 12 inches (305 mm) in the field of the panel.In a blocked diaphragm, continuous panel edges are edges that are aligned from panel to panel rather than offset.
4 For types and nominal thicknesses of walls within a wall group, see Table 2.1.5 For nail size and type, see Sections 6.6.1 and 6.6.4.
Table 6.1. Maximum Nail Spacing for Wood Structural Panel Sheathing in Wood Framed Floor Diaphragms1,2,5
O85573 1.qxd:FPO 85573 1 1/24/08 10:56 AM Page 6-4
6-5
Chapter 6 – Requirements for Connections and Diaphragms
Wind Design
BuildingAspectRatio
Maximum Screw Spacing in Sheathing in Blocked Diaphragms at Locations a/b3 – in.Basic Wind Speed (mph) and Exposure Category
85B 90B 100B 110B 120B 130B 140B 150B 166B 179B 192B85C 90C 100C 110C 120C 130C 140C 150C 163C
85D 90D 100D 110D 120D 130D 140D 150D1 – 1.33 UB UB UB UB UB 6/6 6/6 6/6 4/6 4/6 2.5/4
>1.33 – 1.67 UB UB UB UB 6/6 6/6 4/6 4/6 2.5/4 2.5/4 2.5/4>1.67 – 2 UB UB UB 6/6 6/6 4/6 4/6 2.5/4 2.5/4 2.5/4 2/3
Seismic Design
BuildingAspectRatio
Maximum Screw Spacing in Sheathing in Blocked Diaphragms at Locations a/b3 – in.Seismic Design Category
C D0 D1 D2
Wall Group4 Wall Group4 Wall Group4 Wall Group4
1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 41 – 1.33 UB UB UB UB UB UB UB 6/6 UB UB 6/6 6/6 UB 6/6 6/6 4/6
>1.33 – 1.67 UB UB UB UB UB UB 6/6 6/6 UB 6/6 6/6 4/6 6/6 6/6 4/6 4/6>1.67 – 2 UB UB UB 6/6 UB 6/6 6/6 6/6 6/6 6/6 6/6 4/6 6/6 4/6 4/6 2.5/4
For SI: 1 inch = 25.4 mm; 1 mph = 0.4470 m/s1 UB means unblocked diaphragm permitted2 In unblocked diaphragms, space screws a maximum of 6 inches (152 mm) on center at all supported panel edges, at tension ties, and at continuous
tie locations, where continuous ties are required by Section 6.6.4, and 12 inches (305 mm) on center in the field of the panel. If the applicablebuilding code or AISI/S230 requires closer screw spacing in the field of the panel, the closer spacing shall be used.
3 In blocked diaphragms, maximum screw spacing in inches:a. at diaphragm boundary edges and all continuous panel edges,b. at all other panel edges, at tension ties, and at continuous tie locations, where continuous ties are required by Section 6.6.4, andc. at 12 inches (305 mm) in the field of the panel.In a blocked diaphragm, continuous panel edges are edges that are aligned from panel to panel rather than offset.
4 For types and nominal thicknesses of walls within a wall group, see Table 2.1.5 For screw size, see Sections 6.6.1 and 6.6.4.
Table 6.2. Maximum Screw Spacing for Wood Structural Panel Sheathing in Cold-Formed Steel Framed Floor Diaphragms1,2,5
O85573 1.qxd:FPO 85573 1 1/24/08 10:56 AM Page 6-5
Wind Design
Roof or Ceiling SlopeRise to Run(degrees)
BuildingAspectRatio
Maximum Nail Spacing in Sheathing in Blocked Diaphragms at Locations a/b3 – in.Basic Wind Speed (mph) and Exposure Category
85B 90B 100B 110B 120B 130B 140B 150B 166B 179B 192B85C 90c 100C 110c 120C 130c 140C 150c 163C
85D 90D 100D 110D 120D 130D 140D 150D
0:12 to1:12
(0 to 5)
1 – 1.33 UB UB UB UB UB UB UB UB UB UB UB>1.33 – 1.67 UB UB UB UB UB UB UB UB UB UB UB
>1.67 – 2 UB UB UB UB UB UB UB UB UB UB 6/6
>1:12 to4.4:12
(>5 to 20)
1 – 1.33 UB UB UB UB UB UB UB UB UB UB UB>1.33 – 1.67 UB UB UB UB UB UB UB UB UB 6/6 6/6
>1.67 – 2 UB UB UB UB UB UB UB UB 6/6 6/6 6/6
>4.4:12 to7:12
(>20 to 30)
1 – 1.33 UB UB UB UB UB 6/6 6/6 6/6 4/6 4/6 2.5/4>1.33 – 1.67 UB UB UB UB UB 6/6 6/6 4/6 4/6 2.5/4 2.5/4
>1.67 – 2 UB UB UB UB 6/6 6/6 6/6 4/6 2.5/4 2.5/4 2.5/4
>7:12 to12:12
(>30 to 45)
1 – 1.33 UB UB 6/6 6/6 4/6 2.5/4 2.5/4 2.5/4 DR DR DR>1.33 – 1.67 UB 6/6 6/6 6/6 4/6 2.5/4 2.5/4 2/3 DR DR DR
>1.67 – 2 UB 6/6 6/6 4/6 4/6 2.5/4 2.5/4 2/3 DR DR DR
Seismic Design
BuildingAspectRatio
Maximum Nail Spacing in Sheathing in Blocked Diaphragms at Locations a/b3 – in.Seismic Design Category
C D0 D1 D2
Wall Group4 Wall Group4 Wall Group4 Wall Group4
1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 41 – 1.33 UB UB UB UB UB UB UB 6/6 UB 6/6 6/6 6/6 6/6 6/6 6/6 6/6
>1.33 – 1.67 UB UB UB UB UB UB 6/6 6/6 6/6 6/6 6/6 6/6 6/6 6/6 4/6 4/6>1.67 – 2 UB UB UB UB UB UB 6/6 6/6 6/6 6/6 6/6 6/6 6/6 6/6 4/6 4/6
For SI: 1 inch = 25.4 mm; 1 mph = 0.4470 m/s1 UB means unblocked diaphragm permitted2 In unblocked diaphragms, space nails a maximum of 6 inches (152 mm) on center at all supported panel edges, at tension ties, and at continuous tie
locations, where continuous ties are required by Section 6.6.4, and 12 inches (305 mm) on center in the field of the panel.3 In blocked diaphragms, maximum nail spacing in inches:
a. at diaphragm boundary edges and all continuous panel edges,b. at all other panel edges, at tension ties, and at continuous tie locations, where continuous ties are required by Section 6.6.4, andc. at 12 inches (305 mm) in the field of the panel.In a blocked diaphragm, continuous panel edges are edges that are aligned from panel to panel rather than offset.
4 For types and nominal thicknesses of walls within a wall group, see Table 2.1.5 Applicable building code, or where there is no code AF&PA/WFCM, may require a closer nail spacing in roof sheathing to provide adequate resistance
to wind uplift forces.6 DR means design is required in accordance with the applicable building code, or where there is no code in accordance with AF&PA/WFCM.7 For nail size and type, see Sections 6.6.2 and 6.6.4.
Table 6.3. Maximum Nail Spacing for Wood Structural Panel Sheathing in Wood Framed Roof and Ceiling Diaphragms1,2,5,6,7
6-6
Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
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Wind Design
Roof or Ceiling SlopeRise to Run(degrees)
BuildingAspectRatio
Maximum Screw Spacing in Sheathing in Blocked Diaphragms at Locations a/b3 – in.Basic Wind Speed (mph) and Exposure Category
85B 90B 100B 110B 120B 130B 140B 150B 166B 179B 192B85C 90c 100C 110c 120C 130c 140C 150c 163C
85D 90D 100D 110D 120D 130D 140D 150D
0:12 to1:12
(0 to 5)
1 – 1.33 UB UB UB UB UB UB UB UB UB UB UB>1.33 – 1.67 UB UB UB UB UB UB UB UB UB UB UB
>1.67 – 2 UB UB UB UB UB UB UB UB UB 6/6 6/6
>1:12 to4.4:12
(>5 to 20)
1 – 1.33 UB UB UB UB UB UB UB UB UB UB 6/6>1.33 – 1.67 UB UB UB UB UB UB UB UB 6/6 6/6 6/6
>1.67 – 2 UB UB UB UB UB UB UB 6/6 6/6 6/6 4/6
>4.4:12 to7:12
(>20 to 30)
1 – 1.33 UB UB UB UB 6/6 6/6 6/6 4/6 2.5/4 2.5/4 2.5/4>1.33 – 1.67 UB UB UB UB 6/6 6/6 4/6 4/6 2.5/4 2.5/4 2.5/4
>1.67 – 2 UB UB UB 6/6 6/6 6/6 4/6 4/6 2.5/4 2.5/4 2.5/4
>7:12 to12:12
(>30 to 45)
1 – 1.33 6/6 6/6 6/6 4/6 2.5/4 2.5/4 2.5/4 2/3 2/3 DR DR>1.33 – 1.67 6/6 6/6 6/6 4/6 2.5/4 2.5/4 2.5/4 2/3 DR DR DR
>1.67 – 2 6/6 6/6 4/6 4/6 2.5/4 2.5/4 2.5/4 2/3 DR DR DR
Seismic Design
BuildingAspectRatio
Maximum Screw Spacing in Sheathing in Blocked Diaphragms at Locations a/b3 – in.Seismic Design Category
C D0 D1 D2
Wall Group4 Wall Group4 Wall Group4 Wall Group4
1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 41 – 1.33 UB UB UB UB UB UB UB UB UB UB 6/6 6/6 6/6 6/6 6/6 6/6
>1.33 – 1.67 UB UB UB UB UB UB UB UB UB 6/6 6/6 6/6 6/6 6/6 6/6 6/6>1.67 – 2 UB UB UB UB UB UB 6/6 6/6 UB 6/6 6/6 6/6 6/6 6/6 4/6 4/6
For SI: 1 inch = 25.4 mm; 1 mph = 0.4470 m/s1 UB means unblocked diaphragm permitted2 In unblocked diaphragms, space screws a maximum of 6 inches (152 mm) on center at all supported panel edges, at tension ties, and at continuous
tie locations, where continuous ties are required by Section 6.6.4, and 12 inches (305 mm) on center in the field of the panel. If the applicablebuilding code or AISI/S230 requires closer screw spacing in the field of the panel, the closer spacing shall be used.
3 In blocked diaphragms, maximum screw spacing in inches:a. at diaphragm boundary edges and all continuous panel edges,b. at all other panel edges, at tension ties, and at continuous tie locations, where continuous ties are required by Section 6.6.4, andc. at 12 inches (305 mm) in the field of the panel.In a blocked diaphragm, continuous panel edges are edges that are aligned from panel to panel rather than offset.
4 For types and nominal thicknesses of walls within a wall group, see Table 2.1.5 Applicable building code, or where there is no code AISI/COFS/PM, may require a closer screw spacing in roof sheathing to provide adequate
resistance to wind uplift forces.6 DR means design is required in accordance with the applicable building code, or where there is no code in accordance with AISI/COFS/PM.7 For screw size, see Sections 6.6.2 and 6.6.4.
Table 6.4. Maximum Screw Spacing for Wood Structural Panel Sheathing in Cold-Formed Steel Framed Roof and CeilingDiaphragms1,2,5,6,7
Chapter 6 – Requirements for Connections and Diaphragms
6-7
O85573 1.qxd:FPO 85573 1 1/24/08 10:56 AM Page 6-7
8" (203 mm)minimum
8" (203 mm)minimum
3" (76 mm)minimum
cover
Minimum No. 5 barat 48" (1.2 m) oncenter maximum, or No. 4 bar at 32" (813 mm) on center maximum, if required
Wall form –stay-in-placeor removable
Vertical wallreinforcementas required
Footing
See Section 6.2 foradditional requirementsthat may apply in somecases.
Section Cut through Flat Wall orVertical Core of a Waffle- or
Screen-Grid Wall
Figure 6.1. Foundation wall-to-footing connection.
6-8
Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
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Wall
Footing
Vertical reinforcement extendedor doweled to foundation wherewall height below opening isless than required by Section 6.2
Wall heightbelow lowestadjacentopening morethan requiredby Section 6.2
Vertical wall reinforcementat end of solid wall segment See Section 5.2.2.2
Also, see Figure 6.1
Figure 6.2. Development of vertical steel adjacent to openings in walls.
Chapter 6 – Requirements for Connections and Diaphragms
6-9
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Figure 6.3. Wood framed floor to side of concrete wall, framing perpendicular.
6-10
Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
O85573 1.qxd:FPO 85573 1 1/24/08 10:56 AM Page 6-10
Basic Wind Speed (mph) andExposure Category
Seismic Design Category4
C D0 D1 D2
1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4
12 12 a
12 24
12 36
12 48
16 16 a a a a a a a a a a a a a a a
16 32 a
16 48
19.2 19.2 a a a a a a a a a a a a
19.2 38.4 a a a
85B
90B
100B
110B
120B
130B
140B
150B
166B
179B
192B
85D
90D
100D
110D
120D
130D
140D
150D
85C
90C
100C
110C
120C
130C
140C
150C
163C
Anc
hor
Bolt
Spac
ing
(in.)
Tens
ion
Tie
Spac
ing
(in.)
For SI: 1 inch = 25.4 mm; 1 mph = 0.4470 m/s1 This table is for use with the detail in Figure 6.3. Use of this detail is permitted where cell is not shaded, prohibited where shaded.2 Wall design per other chapters of this Standard is required.3 For wall types and nominal thicknesses within a Wall Group, see Table 2.1.4 Minimum 6-inch (152 mm) nominal wall is required in SDC C through D2. See Section 2.1.1.5 Letter “a” indicates that a minimum nominal 3 x 8-inch (76 x 152 mm) ledger is required.
Figure 6.3 Table. Wood Framed Floor to Side of Concrete Wall, Framing Perpendicular1,2,5
Chapter 6 – Requirements for Connections and Diaphragms
6-11
Wall group3 Wall group3 Wall group3Wall group3
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Figure 6.4. Wood framed floor to side of concrete wall, framing parallel.
6-12
Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
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Basic Wind Speed (mph) andExposure Category
Seismic Design Category4
C D0 D1 D2
1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4
12 12
12 24
12 36
12 48
16 16
16 32
16 48
19.2 19.2
19.2 38.4
24 24
24 48
85B
90B
100B
110B
120B
130B
140B
150B
166B
179B
192B
85D
90D
100D
110D
120D
130D
140D
150D
85C
90C
100C
110C
120C
130C
140C
150C
163C
Anc
hor
Bolt
Spac
ing
(in.)
Tens
ion
Tie
Spac
ing
(in.)
For SI: 1 inch = 25.4 mm; 1 mph = 0.4470 m/s1 This table is for use with the detail in Figure 6.4. Use of this detail is permitted where cell is not shaded, prohibited where shaded.2 Wall design per other chapters of this Standard is required.3 For wall types and nominal thicknesses within a Wall Group, see Table 2.1.4 Minimum 6-inch (152 mm) nominal wall is required in SDC C through D2. See Section 2.1.1.
Figure 6.4 Table. Wood Framed Floor to Side of Concrete Wall, Framing Parallel 1,2
Chapter 6 – Requirements for Connections and Diaphragms
6-13
Wall group3 Wall group3 Wall group3Wall group3
O85573 1.qxd:FPO 85573 1 1/24/08 10:56 AM Page 6-13
Figure 6.5. Wood framed floor to top of concrete wall, framing perpendicular.
6-14
Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
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Basic Wind Speed (mph) andExposure Category
Seismic Design Category4
C D0 D1 D2
1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4
12 126a
6a
8b
8b
8 8 8
12 246a
6a
8
12 36
12 48
16 166a
6b
6b
6b
8 8 8 8
16 326a
6b
16 48
19.2 19.26a
6a
6b
8 8 8
19.2 38.46a
6a
8
24 246a
6b
6b
8 8
24 486a
85B
90B
100B
110B
120B
130B
140B
150B
166B
179B
192B
85D
90D
100D
110D
120D
130D
140D
150D
85C
90C
100C
110C
120C
130C
140C
150C
163C
Anc
hor
Bolt
Spac
ing
(in.)
Tens
ion
Tie
Spac
ing
(in.)
For SI: 1 inch = 25.4 mm; 1 mph = 0.4470 m/s1 This table is for use with the detail in Figure 6.5. Use of this detail is permitted where cell is not shaded, prohibited where shaded.2 Wall design per other chapters of this Standard is required.3 For wall types and nominal thicknesses within a Wall Group, see Table 2.1.4 Minimum 6-inch (152 mm) nominal wall is required in SDC C through D2. See Section 2.1.1.5 For wind design, minimum 4-inch (102 mm) nominal wall is permitted in unshaded cells with no number.6 Numbers 6 (152) and 8 (203) indicate minimum permitted nominal wall thickness in inches (mm) necessary to develop required strength (capacity) of
connection. As a minimum, this nominal thickness shall occur in the portion of the wall indicated by the cross-hatching in Figure 6.5. For theremainder of the wall, see Note 2.
7 Letter “a” indicates that a minimum nominal 3 x 6-inch (76 x 152 mm) sill plate is required. Letter “b” indicates that a 5⁄8” (16 mm) diameter anchorbolt and a minimum nominal 3 x 6-inch (76 x 152 mm) sill plate are required. Use of solutions requiring 5⁄8” (16 mm) bolts are not permitted in SDC Cthrough D2.
Figure 6.5 Table. Wood Framed Floor to Top of Concrete Wall, Framing Perpendicular1,2,5,6,7
Chapter 6 – Requirements for Connections and Diaphragms
6-15
Wall group3 Wall group3 Wall group3Wall group3
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Figure 6.6. Wood framed floor to top of concrete wall, framing parallel.
6-16
Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
O85573 1.qxd:FPO 85573 1 1/24/08 10:56 AM Page 6-16
Basic Wind Speed (mph) andExposure Category
Seismic Design Category4
C D0 D1 D2
1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4
12 126a
6a
8b
8b
8 8 8
12 246a
6a
8
12 36
12 48
16 166a
6b
6b
6b
8 8 8 8
16 326a
6b
16 48
19.2 19.26a
6a
6b
8 8 8
19.2 38.46a
6a
8
24 246a
6b
6b
8 8
24 486a
85B
90B
100B
110B
120B
130B
140B
150B
166B
179B
192B
85D
90D
100D
110D
120D
130D
140D
150D
85C
90C
100C
110C
120C
130C
140C
150C
163C
Anc
hor
Bolt
Spac
ing
(in.)
Tens
ion
Tie
Spac
ing
(in.)
For SI: 1 inch = 25.4 mm; 1 mph = 0.4470 m/s1 This table is for use with the detail in Figure 6.6. Use of this detail is permitted where cell is not shaded, prohibited where shaded.2 Wall design per other chapters of this Standard is required.3 For wall types and nominal thicknesses within a Wall Group, see Table 2.1.4 Minimum 6-inch (152 mm) nominal wall is required in SDC C through D2. See Section 2.1.1.5 For wind design, minimum 4-inch (102 mm) nominal wall is permitted in unshaded cells with no number.6 Numbers 6 (152) and 8 (203) indicate minimum permitted nominal wall thickness in inches (mm) necessary to develop required strength (capacity) of
connection. As a minimum, this nominal thickness shall occur in the portion of the wall indicated by the cross-hatching in Figure 6.6. For theremainder of the wall, see Note 2.
7 Letter “a” indicates that a minimum nominal 3 x 6-inch (76 x 152 mm) sill plate is required. Letter “b” indicates that a 5⁄8” (16 mm) diameter anchorbolt and a minimum nominal 3 x 6-inch (76 x 152 mm) sill plate are required. Use of solutions requiring 5⁄8” (16 mm) bolts are not permitted in SDC Cthrough D2.
Figure 6.6 Table. Wood Framed Floor to Top of Concrete Wall, Framing Parallel 1,2, 5, 6,7
Chapter 6 – Requirements for Connections and Diaphragms
6-17
Wall group3 Wall group3 Wall group3Wall group3
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Figure 6.7. Cold-formed steel floor to side of concrete wall, framing perpendicular.
6-18
Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
O85573 1.qxd:FPO 85573 1 1/24/08 10:56 AM Page 6-18
Basic Wind Speed (mph) andExposure Category
Seismic Design Category4
C D0 D1 D2
1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4
12 12
12 24 6 6 6
12 366 6 6 8
b8b
12 48 6 6 6
16 16
16 326 6 6 8
b16 48 6 6 6
19.2 19.2 6 6
19.2 38.46 6 6 8
b
24 246 6 8
b8b
24 48 6 6 6
85B
90B
100B
110B
120B
130B
140B
150B
166B
179B
192B
85D
90D
100D
110D
120D
130D
140D
150D
85C
90C
100C
110C
120C
130C
140C
150C
163C
Anc
hor
Bolt
Spac
ing
(in.)
Tens
ion
Tie
Spac
ing
(in.)
For SI: 1 inch = 25.4 mm; 1 mph = 0.4470 m/s1 This table is for use with the detail in Figure 6.7. Use of this detail is permitted where cell is not shaded, prohibited where shaded.2 Wall design per other chapters of this Standard is required.3 For wall types and nominal thicknesses within a Wall Group, see Table 2.1.4 Minimum 6-inch (152 mm) nominal wall is required in SDC C through D2. See Section 2.1.1.5 For wind design, minimum 4-inch (102 mm) nominal wall is permitted in unshaded cells with no number.6 Numbers 6 (152) and 8 (203) indicate minimum permitted nominal wall thickness in inches (mm) necessary to develop required strength (capacity) of
connection. As a minimum, this nominal thickness shall occur in the portion of the wall indicated by the cross-hatching in Figure 6.7. For theremainder of the wall, see Note 2.
7 Letter “b” indicates a 5⁄8” (16 mm) diameter anchor bolt is required. Use of solutions requiring 5⁄8” (16 mm) bolts are not permitted in SDC C throughD2.
Figure 6.7 Table. Cold-Formed Steel Framed Floor to Side of Concrete Wall, Framing Perpendicular1,2,5,6,7
Chapter 6 – Requirements for Connections and Diaphragms
6-19
Wall group3 Wall group3 Wall group3Wall group3
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Figure 6.8. Cold-formed steel floor to side of concrete wall, framing parallel.
6-20
Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
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Basic Wind Speed (mph) andExposure Category
Seismic Design Category4
C D0 D1 D2
1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4
12 12
12 24 6 6 6
12 366 6 6 8
b8b
12 48
16 16
16 326 6 6 8
b16 48 6 6 6
19.2 19.2 6 6
19.2 38.46 6 6 8
b
24 246 6 8
b8b
24 48 6 6 6
85B
90B
100B
110B
120B
130B
140B
150B
166B
179B
192B
85D
90D
100D
110D
120D
130D
140D
150D
85C
90C
100C
110C
120C
130C
140C
150C
163C
Anc
hor
Bolt
Spac
ing
(in.)
Tens
ion
Tie
Spac
ing
(in.)
For SI: 1 inch = 25.4 mm; 1 mph = 0.4470 m/s1 This table is for use with the detail in Figure 6.8. Use of this detail is permitted where cell is not shaded, prohibited where shaded.2 Wall design per other chapters of this Standard is required.3 For wall types and nominal thicknesses within a Wall Group, see Table 2.1.4 Minimum 6-inch (152 mm) nominal wall is required in SDC C through D2. See Section 2.1.1.5 For wind design, minimum 4-inch (102 mm) nominal wall is permitted in unshaded cells with no number.6 Numbers 6 (152) and 8 (203) indicate minimum permitted nominal wall thickness in inches (mm) necessary to develop required strength (capacity) of
connection. As a minimum, this nominal thickness shall occur in the portion of the wall indicated by the cross-hatching in Figure 6.8. For theremainder of the wall, see Note 2.
7 Letter “b” indicates a 5⁄8” (16 mm) diameter anchor bolt is required. Use of solutions requiring 5⁄8” (16 mm) bolts are not permitted in SDC C throughD2.
Figure 6.8 Table. Cold-Formed Steel Framed Floor to Side of Concrete Wall, Framing Parallel1,2,5,6,7
Chapter 6 – Requirements for Connections and Diaphragms
6-21
Wall group3 Wall group3 Wall group3Wall group3
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Figure 6.9. Cold-formed steel floor to top of concrete wall, framing perpendicular.
6-22
Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
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Basic Wind Speed (mph) andExposure Category
Seismic Design Category4
C D0 D1 D2
1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4
12 126a
6a
8b
8b
8 8
12 246a
6b
8b
8b
8 8
16 166a
6b
8b
8b
8 8
16 326a
6b
8b
8b
8 8
19.2 19.26a
8b
8b
8b
8 8 8
19.2 38.46a
8b
8b
8b
24 246a
8b
8b
8 8
85B
90B
100B
110B
120B
130B
140B
150B
166B
179B
192B
85D
90D
100D
110D
120D
130D
140D
150D
85C
90C
100C
110C
120C
130C
140C
150C
163C
Anc
hor
Bolt
Spac
ing
(in.)
Tens
ion
Tie
Spac
ing
(in.)
For SI: 1 inch = 25.4 mm; 1 mph = 0.4470 m/s1 This table is for use with the detail in Figure 6.9. Use of this detail is permitted where cell is not shaded, prohibited where shaded.2 Wall design per other chapters of this Standard is required.3 For wall types and nominal thicknesses within a Wall Group, see Table 2.1.4 Minimum 6-inch (152 mm) nominal wall is required in SDC C through D2. See Section 2.1.1.5 For wind design, minimum 4-inch (102 mm) nominal wall is permitted in unshaded cells with no number.6 Numbers 6 (152) and 8 (203) indicate minimum permitted nominal wall thickness in inches (mm) necessary to develop required strength (capacity) of
connection. As a minimum, this nominal thickness shall occur in the portion of the wall indicated by the cross-hatching in Figure 6.9. For theremainder of the wall, see Note 2.
7 Letter “a” indicates that a minimum nominal 3 x 6-inch (72 X 152 mm) sill plate is required. Letter “b” indicates that a 5⁄8” (16 mm) diameter anchorbolt and a minimum nominal 3 x 6-inch (72 x 152 mm) sill plate are required. Use of solutions requiring 5⁄8” (16 mm) bolts are not permitted in SDC Cthrough D2.
Figure 6.9 Table. Cold-Formed Steel Framed Floor to Top of Concrete Wall, Framing Perpendicular1,2,5,6,7
Chapter 6 – Requirements for Connections and Diaphragms
6-23
Wall group3 Wall group3 Wall group3Wall group3
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Figure 6.10. Cold-formed steel floor to top of concrete wall, framing parallel.
6-24
Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
O85573 1.qxd:FPO 85573 1 1/24/08 10:57 AM Page 6-24
Basic Wind Speed (mph) andExposure Category
Seismic Design Category4
C D0 D1 D2
1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4
12 126a
6b
8b
8b
8 8
12 246a
6b
8b
8b
8 8
16 166a
6b
8b
8b
8 8
16 326a
6b
8b
8b
8 8
19.2 19.26a
8b
8b
8b
8 8 8
19.2 38.46a
8b
8b
8b
24 246a
8b
8b
8 8
85B
90B
100B
110B
120B
130B
140B
150B
166B
179B
192B
85D
90D
100D
110D
120D
130D
140D
150D
85C
90C
100C
110C
120C
130C
140C
150C
163C
Anc
hor
Bolt
Spac
ing
(in.)
Tens
ion
Tie
Spac
ing
(in.)
For SI: 1 inch = 25.4 mm; 1 mph = 0.4470 m/s1 This table is for use with the detail in Figure 6.10. Use of this detail is permitted where cell is not shaded, prohibited where shaded.2 Wall design per other chapters of this Standard is required.3 For wall types and nominal thicknesses within a Wall Group, see Table 2.1.4 Minimum 6-inch (152 mm) nominal wall is required in SDC C through D2. See Section 2.1.1.5 For wind design, minimum 4-inch (102 mm) nominal wall is permitted in unshaded cells with no number.6 Numbers 6 (152) and 8 (203) indicate minimum permitted nominal wall thickness in inches (mm) necessary to develop required strength (capacity) of
connection. As a minimum, this nominal thickness shall occur in the portion of the wall indicated by the cross-hatching in Figure 6.10. For theremainder of the wall, see Note 2.
7 Letter “a” indicates that a minimum nominal 3 x 6-inch (72 x 152 mm) sill plate is required. Letter “b” indicates that a 5⁄8” (16 mm) diameter anchorbolt and a minimum nominal 3 x 6-inch (72 x 152 mm) sill plate are required. Use of solutions requiring 5⁄8” (16 mm) bolts are not permitted in SDC Cthrough D2.
Figure 6.10 Table. Cold-Formed Steel Framed Floor to Top of Concrete Wall, Framing Parallel1,2,5,6,7
Chapter 6 – Requirements for Connections and Diaphragms
6-25
Wall group3 Wall group3 Wall group3Wall group3
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Figure 6.11. Wood framed roof to top of concrete wall, framing perpendicular.
6-26
Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
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Basic Wind Speed (mph) andExposure Category
Seismic Design Category4
C D0 D1 D2
1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4
12 126 6
a6b
8b
8 8
12 24 6
12 36
12 48
16 166 6
a6b
8b
8b
16 32 6
16 48
19.2 19.26 6
a6b
8b
8b
19.2 38.4 6
24 246a
6a
6b
8b
8b
8
24 48
85B
90B
100B
110B
120B
130B
140B
150B
166B
179B
192B
85D
90D
100D
110D
120D
130D
140D
150D
85C
90C
100C
110C
120C
130C
140C
150C
163C
Anc
hor
Bolt
Spac
ing
(in.)
Tens
ion
Tie
Spac
ing
(in.)
For SI: 1 inch = 25.4 mm; 1 mph = 0.4470 m/s1 This table is for use with the detail in Figure 6.11. Use of this detail is permitted where cell is not shaded, prohibited where shaded.2 Wall design per other chapters of this Standard is required.3 For wall types and nominal thicknesses within a Wall Group, see Table 2.1.4 Minimum 6-inch (152 mm) nominal wall is required in SDC C through D2. See Section 2.1.1.5 For wind design, minimum 4-inch (102 mm) nominal wall is permitted in unshaded cells with no number.6 Numbers 6 (152) and 8 (203) indicate minimum permitted nominal wall thickness in inches (mm) necessary to develop required strength (capacity) of
connection. As a minimum, this nominal thickness shall occur in the portion of the wall indicated by the cross-hatching in Figure 6.11. For theremainder of the wall, see Note 2.
7 Letter “a” indicates that a minimum nominal 3 x 6-inch (72 x 152 mm) sill plate is required. Letter “b” indicates that a 5⁄8” (16 mm) diameter anchorbolt and a minimum nominal 3 x 6-inch (72 x 152 mm) sill plate are required. Use of solutions requiring 5⁄8” (16 mm) bolts are not permitted in SDC Cthrough D2.
Figure 6.11 Table. Wood Framed Roof to Top of Concrete Wall, Framing Perpendicular1,2,5,6,7
Chapter 6 – Requirements for Connections and Diaphragms
6-27
Wall group3 Wall group3 Wall group3Wall group3
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Figure 6.12. Wood framed roof to top of concrete wall, framing parallel.
6-28
Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
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Basic Wind Speed (mph) andExposure Category
Seismic Design Category4
C D0 D1 D2
1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4
12 126 6 6
a8b
8b
8 8
12 246 6 6
a8b
8b
8 8
12 366 6 6
a8b
8b
8 8
12 486 6 6
a8b
8b
8 8 8
16 166 6 6
a8b
8b
8b
8 8 8
16 326 6 6
a8b
8b
8b
8 8 8
16 486 6 6
a8b
8b
8b
8 8 8
19.2 19.26 6 6
a8b
8b
8b
19.2 38.46 6 6
a8b
8b
8b
24 246 6
a6a
6b
8b
8
24 486 6
a6a
6b
8b
8
85B
90B
100B
110B
120B
130B
140B
150B
166B
179B
192B
85D
90D
100D
110D
120D
130D
140D
150D
85C
90C
100C
110C
120C
130C
140C
150C
163C
Anc
hor
Bolt
Spac
ing
(in.)
Tens
ion
Tie
Spac
ing
(in.)
For SI: 1 inch = 25.4 mm; 1mph = 0.4470 m/s1 This table is for use with the detail in Figure 6.12. Use of this detail is permitted where cell is not shaded, prohibited where shaded.2 Wall design per other chapters of this Standard is required.3 For wall types and nominal thicknesses within a Wall Group, see Table 2.1.4 Minimum 6-inch (152 mm) nominal wall is required in SDC C through D2. See Section 2.1.1.5 For wind design, minimum 4-inch (102 mm) nominal wall is permitted in unshaded cells with no number.6 Numbers 6 (152) and 8 (203) indicate minimum permitted nominal wall thickness in inches (mm) necessary to develop required strength (capacity) of
connection. As a minimum, this nominal thickness shall occur in the portion of the wall indicated by the cross-hatching in Figure 6.12. For theremainder of the wall, see Note 2.
7 Letter “a” indicates that a minimum nominal 3 x 6-inch (72 x 152 mm) sill plate is required. Letter “b” indicates that a 5⁄8” (16 mm) diameter anchorbolt and a minimum nominal 3 x 6-inch (72 x 152 mm) sill plate are required. Use of solutions requiring 5⁄8” (16 mm) bolts are not permitted in SDC Cthrough D2.
Figure 6.12 Table. Wood Framed Roof to Top of Concrete Wall, Framing Parallel 1,2,5,6,7
Chapter 6 – Requirements for Connections and Diaphragms
6-29
Wall group3 Wall group3 Wall group3Wall group3
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Figure 6.13. Cold-formed steel roof to top of concrete wall, framing perpendicular.
6-30
Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
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Basic Wind Speed (mph) andExposure Category
Seismic Design Category4
C D0 D1 D2
1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4
12 126 6 8
b8b
8 8
12 246 6 8
b8b
8 8 8
16 166 6 8
b8b
8 8 8
16 326 6 8
b8b
8 8
19.2 19.26 6 8
b8b
8 8 8
19.2 38.46 6 8
b8b
24 246 6 8
b8
85B
90B
100B
110B
120B
130B
140B
150B
166B
179B
192B
85D
90D
100D
110D
120D
130D
140D
150D
85C
90C
100C
110C
120C
130C
140C
150C
163C
Anc
hor
Bolt
Spac
ing
(in.)
Tens
ion
Tie
Spac
ing
(in.)
For SI: 1 inch = 25.4 mm; 1 mph = 0.4470 m/s1 This table is for use with the detail in Figure 6.13. Use of this detail is permitted where cell is not shaded, prohibited where shaded.2 Wall design per other chapters of this Standard is required.3 For wall types and nominal thicknesses within a Wall Group, see Table 2.1.4 Minimum 6-inch (152 mm) nominal wall is required in SDC C through D2. See Section 2.1.1.5 For wind design, minimum 4-inch (102 mm) nominal wall is permitted in unshaded cells with no number.6 Numbers 6 (152) and 8 (203) indicate minimum permitted nominal wall thickness in inches (mm) necessary to develop required strength (capacity) of
connection. As a minimum, this nominal thickness shall occur in the portion of the wall indicated by the cross-hatching in Figure 6.13. For theremainder of the wall, see Note 2.
7 Letter “b” indicates that a 5⁄8” (16 mm) diameter anchor bolt and a minimum nominal 3 x 6-inch (72 x 152 mm) sill plate are required. Use ofsolutions requiring 5⁄8” (16 mm) bolts are not permitted in SDC C through D2.
Figure 6.13 Table. Cold-Formed Steel Framed Roof to Top of Concrete Wall, Framing Perpendicular1,2,5,6,7
Chapter 6 – Requirements for Connections and Diaphragms
6-31
Wall group3 Wall group3 Wall group3Wall group3
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Figure 6.14. Cold-formed steel roof to top of concrete wall, framing parallel.
6-32
Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
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Basic Wind Speed (mph) andExposure Category
Seismic Design Category4
C D0 D1 D2
1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4
12 126 6 8
b8 8
12 246 6 8
b8 8 8
16 166 8
b8b
8 8 8
16 326 8
b8b
8 8
19.2 19.26 6 8
b8b
8 8 8
19.2 38.46 6 8
b8b
24 246 6 8
b8b
8
85B
90B
100B
110B
120B
130B
140B
150B
166B
179B
192B
85D
90D
100D
110D
120D
130D
140D
150D
85C
90C
100C
110C
120C
130C
140C
150C
163C
Anc
hor
Bolt
Spac
ing
(in.)
Tens
ion
Tie
Spac
ing
(in.)
For SI: 1 inch = 25.4 mm; 1 mph = 0.4470 m/s1 This table is for use with the detail in Figure 6.14. Use of this detail is permitted where cell is not shaded, prohibited where shaded.2 Wall design per other chapters of this Standard is required.3 For wall types and nominal thicknesses within a Wall Group, see Table 2.1.4 Minimum 6-inch (152 mm) nominal wall is required in SDC C through D2. See Section 2.1.1.5 For wind design, minimum 4-inch (102 mm) nominal wall is permitted in unshaded cells with no number.6 Numbers 6 (152) and 8 (203) indicate minimum permitted nominal wall thickness in inches (mm) necessary to develop required strength (capacity) of
connection. As a minimum, this nominal thickness shall occur in the portion of the wall indicated by the cross-hatching in Figure 6.14. For theremainder of the wall, see Note 2.
7 Letter “b” indicates that a 5⁄8” (16 mm) diameter anchor bolt is required. Use of solutions requiring 5⁄8” (16 mm) bolts are not permitted in SDC Cthrough D2.
Figure 6.14 Table. Cold-Formed Steel Framed Roof to Top of Concrete Wall, Framing Parallel1,2,5,6,7
Chapter 6 – Requirements for Connections and Diaphragms
6-33
Wall group3 Wall group3 Wall group3Wall group3
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Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
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7-1
Chapter 7Requirements for Lintels andReinforcement Around Openings
7.1 REINFORCEMENT AROUNDOPENINGSReinforcement shall be provided around openings in wallsequal to or greater than 2 feet (610 mm) in width in accor-dance with this section and Figure 7.1, in addition to theminimum wall reinforcement required by Chapters 3, 4 and5. Vertical wall reinforcement required by this section ispermitted to be used as reinforcement at the ends of solidwall segments required by Section 5.2.2.2 provided it islocated in accordance with Section 7.1.2. Wall openings shallhave a minimum depth of concrete over the width of theopening of 8 inches (203 mm) in flat walls and waffle-gridwalls, and 12 inches (305 mm) in screen-grid walls. Wallopenings in waffle-grid and screen-grid walls shall be locatedsuch that no less than one-half of a vertical core occursalong each side of the opening.
7.1.1 Horizontal ReinforcementLintels complying with Section 7.2 shall be provided abovewall openings equal to or greater than 2 feet (610 mm) inwidth.
Exception: Continuous horizontal wall reinforcementplaced within 12 inches (305 mm) of the top of the wallstory as required in Chapters 3 and 4 is permitted to beused in lieu of top or bottom lintel reinforcement requiredby Section 7.2 provided that the continuous horizontalwall reinforce ment meets the location requirements speci-fied in Figures 7.3, 7.4, and 7.5 and the size requirementsspecified in Tables 7.3 through 7.25.
Openings equal to or greater than 2 feet (610 mm) in widthshall have a minimum of one No. 4 bar placed within 12inches (305 mm) of the bottom of the opening. SeeFigure 7.1.
Horizontal reinforcement placed above and below anopening shall extend beyond the edges of the opening thedimension required to develop the bar in tension inaccordance with Section 2.5.4.
7.1.2 Vertical ReinforcementIn all buildings where the factored roof uplift force fromTable 7.1A is less than or equal to 800 plf (11.68 kN/m) andthe opening width is equal to or greater than 2 feet (610mm) and less than or equal to 18 feet (5.5 m), not less thanone No. 4 bar (Grade 40 (280 MPa)) shall be provided oneach side of the opening. Where the roof uplift force fromTable 7.1A is greater than 800 plf (11.68 kN/m) and theopening width is greater than 6 feet (1.8 m), vertical rein -forcement shall be provided on each side of openings inaccordance with Table 7.1B.
In multiple dwellings assigned to Seismic Design Category C,and all buildings assigned to Seismic Design Category D0, D1
or D2, vertical reinforcement shall comply with the above re -quirements, but shall not be less than 2 No. 4 bars (Grade 60)or one No. 5 bar (Grade 60 (420 MPa)). See Section 4.1.3.
The vertical reinforcement required by this section shallextend the full height of the wall story and shall be locatedwithin 12 inches (305 mm) of each side of the opening. Thevertical reinforcement required on each side of an openingby this section is permitted to serve as reinforcement at theends of solid wall segments in accordance with Section5.2.2.2, provided it is located as required by the applicabledetail in Figure 5.1. Where the vertical reinforcement requiredby this section is used to satisfy the requirements of Section5.2.2.2 in waffle- and screen-grid walls, a concrete flangeshall be created at the ends of the solid wall segments inaccordance with Table 5.4B, footnote 9. In the top moststory, the reinforcement shall terminate in accordance withSection 4.1.6.
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Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
7-2
7.1.3 Wall Segments in Seismic DesignCategories C, D0, D1 and D2
For multiple dwellings assigned to Seismic Design CategoryC and all buildings assigned to Seismic Design Category D0,D1 or D2, wall segments with a length of less than 24 inches(610 mm), shall be provided with not less than No. 3 ties inaccordance with Figure 7.2. Ties shall be terminated at eachend with a standard hook conforming to Figure 2.6.
Exception: Ties need not be provided in wall segmentswhere flat walls are used to provide all of the requiredsolid wall length.
Ties shall start at d/4 but not more than 3 inches (76 mm)from the top and bottom of the wall segment. Ties shall bespaced at d/2, but not more than 6 inches (152 mm) oncenter along the height of the wall segment. Wherenecessary to provide a minimum cover of 11⁄2 inches (38 mm)on all sides of ties, screen- and waffle-grid forms shall bemodified by removal of form material, or replaced by flatforms. Ties required by this section are permitted to be usedto satisfy the horizontal reinforcement requirements ofSection 4.1.3.
7.2 LINTELSLintels shall be provided over all openings equal to or greaterthan 2 feet (610 mm) in width. Lintels with uniform loadingshall conform to Sections 7.2.1, 7.2.2, and 7.2.3 or Section7.2.4. Lintels supporting concentrated loads, such as fromroof or floor beams or girders, shall be designed in accor -dance with the applicable building code, or if there is nocode in accordance with ACI 318.
7.2.1 Lintels Designed for Gravity Load-Bearing ConditionsWhere a lintel will be subjected to gravity load condition 1through 5 of Table 7.2, the clear span of the lintel shall notexceed that permitted by Tables 7.3 through 7.16. Themaximum clear span of lintels with and without stirrups inflat walls shall be determined in accordance with Tables 7.3through 7.10, and constructed in accordance with Figure7.3. The maximum clear span of lintels with and without stir-rups in waffle-grid walls shall be determined in accordancewith Tables 7.11 through 7.14, and constructed in accor -dance with Figure 7.4. The maximum clear span of lintelswith and without stirrups in screen-grid walls shall be deter-mined in accordance with Tables 7.15 and 7.16, and con -structed in accordance with Figure 7.5. The clear span of a
lintel subjected to gravity loading conditions and upliftloading conditions (see Section 7.2.2) shall not exceed thesmaller of the spans determined for the two conditions.
Where required by the applicable table, No. 3 stirrups shallbe installed in lintels at a maximum spacing of d/2 where dequals the depth of the lintel, D, less the cover of theconcrete as shown in Figures 7.3, 7.4, and 7.5. The smallervalue of d computed for the top and bottom bar shall beused to determine the maximum stirrup spacing. Where stir-rups are required in a lintel with a single bar or two bundledbars in the top and bottom, they shall be fabricated like theletter “c” or “s” with 135-degree standard hooks at eachend that comply with Section 2.5.5 and Figure 2.6 andinstalled as shown in Figures 7.3 through 7.5. Where twobars are required in the top and bottom of the lintel and thebars are not bundled, the bars shall be separated by aminimum of 1 inch (25 mm), and stirrups shall be fabricatedwith 90- or 135-degree standard hooks that comply withSection 2.5.5 and Figure 2.6 and installed as shown inFigures 7.3 and 7.4. For flat, waffle-grid and screen-gridlintels, stirrups are not required in center distance, A, portionof spans in accordance with Figure 7.1 and Tables 7.3through 7.16, and Tables 7.19 through 7.25.
7.2.2 Lintels Designed for Uplift LoadingConditionsWhere the roof uplift force in Table 7.1A exceeds 600 plf(8.76 kN/m), the clear span of a lintel in the top story of atwo-story building or first story of a one story building sup -porting roof framing members shall not exceed that permittedby Tables 7.19 through 7.25 based on the uplift force fromTable 7.1A. Where the roof uplift force in Table 7.1A exceeds600 plf (8.76 kN/m), the clear span of a lintel in the firststory of a two-story building or basement of a one-storybuilding supporting an exterior wall of light framed construc-tion which supports roof framing members shall not exceedthat permitted by Tables 7.19 through 7.25 based on theuplift force from Table 7.1A. Where the roof uplift force inTable 7.1A exceeds 965 plf (14.09 kN/m), the clear span of alintel in the first story of a two-story building or basement ofa one-story building supporting an exterior wall of concreteconstruction which supports roof framing members shall notexceed that permitted by Tables 7.19 through 7.25 based onthe uplift force from Table 7.1A, less the factored dead loadin the table below. If the net uplift force is less than or equalto 600 plf (8.76 kN/m) after subtracting the value from thetable below from the force from Table 7.1A, the lintel is notrequired to be designed for uplift loads.
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7-3
The maximum clear span of lintels with and without stirrupsin flat walls for uplift loading conditions shall be determinedin accordance with Tables 7.19 through 7.22, and con -structed in accordance with Figure 7.3. The maximum clearspan of lintels with and without stirrups in waffle-grid wallsfor uplift loading conditions shall be determined in accor dancewith Tables 7.23 and 7.24, and constructed in accordancewith Figure 7.4. The maximum clear span of lintels with andwithout stirrups in screen-grid walls for uplift loading condi-tions shall be determined in accordance with Table 7.25, andconstructed in accordance with Figure 7.5. The clear span ofa lintel subjected to uplift loading conditions and gravityloading conditions (see Section 7.2.1) shall not exceed thesmaller of the spans determined for the two conditions.
7.2.3 Bundled Bars in LintelsIt is permitted to bundle two bars in contact with each otherin lintels if all of the following are observed:
1. Bars no larger than No. 6 are bundled.
2. Where the wall thickness is not sufficient to provide notless than 3 inches (76 mm) of clear space beside bars(total on both sides) oriented horizontally in a bundle,the bundled bars shall be oriented in a vertical plane.
3. Where vertically oriented bundled bars terminate withstandard hooks to develop the bars in tension beyondthe support (see Section 2.5.4), the hook extensions shallbe staggered to provide a minimum of one inch (25 mm)clear spacing between the extensions.
4. Bundled bars shall not be lap spliced within the lintelspan and the length on each end of the lintel that isrequired to develop the bars in tension.
5. Bundled bars shall be enclosed within stirrupsthroughout the length of the lintel. Stirrups and theinstallation thereof shall comply with Section 7.2.1.
7.2.4 Lintels Without Stirrups Designed forNon Load-Bearing ConditionsThe maximum clear span of lintels without stirrups designedfor nonload-bearing conditions of Table 7.2 shall be deter -mined in accordance with this section. The maximum clearspan of lintels without stirrups in flat walls shall bedetermined in accordance with Table 7.17, and themaximum clear span of lintels without stirrups in walls ofwaffle-grid or screen-grid construction shall be determined inaccordance with Table 7.18.
7.2.5 Lintels in Seismic Design Categories C,D0, D1 and D2
For multiple dwellings assigned to Seismic Design CategoryC and all buildings assigned to Seismic Design Category D0,D1 or D2, lintels with a depth, D, less than 24 inches (610mm) shall be provided with not less than No. 3 stirrups inaccordance with Figure 7.2. Stirrups shall be terminated ateach end with a standard hook conforming to Figure 2.6.
Exception: Stirrup reinforcing for lintels where flat wallsare used to provide all of the required solid wall lengthneed only comply with Section 7.2.1.
Stirrups shall start at d/4, but not more than 3 inches(76 mm) from each end of the lintel. Stirrups shall be spacedat d/2, but not more than 6 inches (152 mm) on centeracross the entire length of the lintel. Where necessary toprovide a minimum cover of 11⁄2 inches (38 mm) on all sidesof stirrups, screen- and waffle-grid forms shall be modifiedby removal of form material, or replaced by flat forms. Stir -rups required by this section are permitted to be used tosatisfy the stirrup requirements of Section 7.2.1.
Chapter 7 – Requirements for Lintels and Reinforcement Around Openings
Wall Group1 ofconcrete wall in storyabove supported by
lintel
Factored dead load tobe subtracted from force
determined fromTable 7.1A (plf)
1 325
2 505
3 690
4 875
For SI: 1 plf = 0.0146 kN/m.1. See Table 2.1 for types of walls within a group.
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Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
7-4
Table 7.1A. Factored Roof Uplift Force2,3,4
Sidewalllength,L1 (ft)
Endwalllength,W1 (ft)
Basic wind speed (mph) and exposure category
85B 90B 100B 110B 120B 130B 140B 150B 166B 179B 192B
— — 85C 90C 100C 110C 120C 130C 140C 150C 163C
— — — 85D 90D 100D 110D 120D 130D 140D 150D
Velocity pressure, q (psf)
11.51 12.90 15.95 19.28 22.94 26.92 31.79 37.41 43.90 50.91 58.45
Factored roof unlift force at top of exterior wall (plf)
Portions of wall less than or equal to 2a from corner where roof slope is < 5.6 in 12 (< 25 degrees)
all
15
20
30
40
Additional uplift to be added per foot of horizontal projection of roof overhang (plf)
all ≤ 40 25 29 37 47 57 68 82 98 116 135 156
Portions of wall greater than 2a from corner where roof slope is < 5.6 in 12 (< 25 degrees) andall portions of wall where roof slope is ≥ 5.6 in 12 (≥ 25 degrees)
all
15
20
30
≤ 30 40
≥ 40 40
Additional uplift to be added per foot of horizontal projection of roof overhang (plf)
all ≤ 40 13 15 20 26 32 39 47 57 68 80 93
For SI: 1 foot = 0.3048 m; 1 psf = 0.0479 kN/m2; 1 plf = 0.0146 kN/m; 1 mph = 0.4470 m/s1. For intermediate values of sidewall length, endwall length and basic wind speed, use the larger uplift value or determine by interpolation. 2. Distance “a” is 10% of the least horizontal dimension of the building or 0.4 times the mean roof height, whichever is smaller, but not less than
3 feet (914 mm).3. Values in table are based on a roof ceiling dead load of 15 psf (0.72 kN/m2).4. Values in table are based on a building with a mean roof height of 35 feet (10.7 m). For buildings with a mean roof height of less than 35 feet
(10.7 m), tabulated values are permitted to be reduced by multiplying by the appropriate factor from Table 5.2.
Table 7.1B. Number, Size and Grade of Vertical Reinforcement on Each Side of Opening1
Openingwidth (ft)
Factored roof uplift force from Table 7.1A (plf)≤ 800 1,000 1,200 1,400 1,600 1,800 2,000 2,200
No. of bars – bar size No./Grade of reinforcement≥ 2 and ≤ 6 1 – 4/40
8 1 – 4/40 1 – 4/60
10 1 – 4/40 1 – 4/60 1 – 5/40
12 1 – 4/40 1 – 4/60 2 – 4/40 or 1 – 6/40
14 1 – 4/40 1 – 4/60 1 – 5/40 2 – 4/40 or 1 – 6/40 1 – 5/60
16 1 – 4/40 1 – 4/60 2 – 4/40 or 1 – 6/40 1 – 5/60 2 – 4/60 or 1– 6/60
18 1 – 4/40 1 – 4/60 2 – 4/40 or 1 – 6/40 1 – 5/60 2 – 4/60 or 1 – 6/60
For SI: 1 plf = 0.0146 kN/m; 1 ft = 0.3048 m; 1 mph = 0.4470 m/s; Grade 40 = 280 MPa; Grade 60 = 420 MPa1 Minimum yield strength of reinforcement required for buildings assigned to Seismic Design Category D0, D1 or D2 is 60,000 psi (420 MPa). See
Section 4.1.3.
57
85
113
151
76
101
151
202
117
157
235
313
163
217
326
435
213
284
426
569
268
357
536
714
335
446
669
892
412
549
823
1098
501
667
1001
1335
597
796
1193
1591
700
933
1400
1867
52
61
76
89
101
71
85
109
133
146
112
136
183
228
244
156
193
263
332
351
205
255
352
446
469
258
323
448
570
597
323
406
566
722
754
398
502
701
898
935
485
612
858
1100
1144
579
731
1028
1319
1370
679
860
1210
1554
1613
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7-5
Chapter 7 – Requirements for Lintels and Reinforcement Around Openings
Table 7.2. Lintel Design Loading Conditions1,2,4
Description of loads and openings above influencing design of lintelDesignloading
condition3
Opening in wall of top story of two-story building, or first story of one-story building
Wall supporting loads from roof,including attic floor, if applicable, and
top of lintel equal to or less than W/2 below top of wall 2
top of lintel greater than W/2 below top of wall NLB
Wall not supporting loads from roof or attic floor NLB
Opening in wall of first story of two-story building where wall immediately above is of concrete construction, oropening in basement wall of one-story building where wall immediately above is of concrete construction
LB ledger board mounted to side ofwall with bottom of ledger less than orequal to W/2 above top of lintel, and
top of lintel greater than W/2 below bottom of opening in story above 1
top of lintel less than or equal to W/2 below bottomof opening in story above,
and
opening is entirely within the footprintof the opening in the story above
1
opening is partially within the footprintof the opening in the story above
4
LB ledger board mounted to side of wall with bottom of ledger more than W/2 above top of lintel NLB
NLB ledger board mounted to side ofwall with bottom of ledger less than orequal to W/2 above top of lintel, or noledger board, and
top of lintel greater than W/2 below bottom of opening in story above NLB
top of lintel less than or equal to W/2 below bottomof opening in story above,
and
opening is entirely within the footprintof the opening in the story above
NLB
opening is partially within the foot printof the opening in the story above
1
Opening in basement wall of two-story building where walls of two stories above are of concrete construction
LB ledger board mounted to side ofwall with bottom of ledger less than orequal to W/2 above top of lintel, and
top of lintel greater than W/2 below bottom of opening in story above 1
top of lintel less than or equal to W/2 below bottomof opening in story above,
and
opening is entirely within the footprintof the opening in the story above
1
opening is partially within the footprintof the opening in the story above
5
LB ledger board mounted to side of wall with bottom of ledger more than W/2 above top of lintel NLB
NLB ledger board mounted to side ofwall with bottom of ledger less than orequal to W/2 above top of lintel, or noledger board, and
top of lintel greater than W/2 below bottom of opening in story above NLB
top of lintel less than or equal to W/2 below bottomof opening in story above,
and
opening is entirely within the footprintof the opening in the story above
NLB
opening is partially within the footprintof the opening in the story above
1
Opening in wall of first story of two-story building where wall immediately above is of light framed construction,or opening in basement wall of one-story building, where wall immediately above is of light framed construction
Wall supporting loads from roof,second floor and top-story wall oflight-framed construction, and
top of lintel equal to or less than W/2 below top of wall 3
top of lintel greater than W/2 below top of wall NLB
Wall not supporting loads from roof or second floor NLB
1 LB means load bearing, NLB means non-load bearing, and W means width of opening.2 Footprint is the area of the wall below an opening in the story above, bounded by the bottom of the opening and vertical lines extending down-
ward from the edges of the opening.3 For design loading condition “NLB” see Tables 7.17 and 7.18. For all other design loading conditions see Tables 7.3 through 7.16.4 A NLB ledger board is a ledger attached to a wall that is parallel to the span of the floor, roof or ceiling framing that supports the edge of the
floor, ceiling or roof.
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Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
7-6
Table 7.3. Maximum Allowable Clear Spans for 4-inch Nominal Thick Flat Lintels in Load-Bearing Walls1,2,3,4,5,6,13
Roof Clear Span 40 feet and Floor Clear Span 32 feet
LintelDepth7, D
(in.)
Number of barsand bar sizein top and
bottom of lintel
Steel yieldstrength8,
fy (psi)
Loading condition determined from Table 7.2
12 3 4 5
Maximum ground snow load (psf)30 70 30 70 30 70 30 70
8
Span without stirrups9,10 3-2 3-4 2-4 2-6 2-2 2-1 2-0 2-0 2-0
1 – #440,000 5-2 5-5 4-1 4-3 3-10 3-7 3-4 2-9 2-960,000 6-2 6-5 4-11 5-1 4-6 4-2 3-8 2-11 2-10
1 – #540,000 6-3 6-7 5-0 5-2 4-6 4-2 3-8 2-11 2-1060,000 DR DR DR DR DR DR DR DR DR
Center distance A11,12 1-1 1-2 0-8 0-9 0-7 0-6 0-5 0-4 0-4
12
Span without stirrups9,10 3-4 3-7 2-9 2-11 2-8 2-6 2-5 2-2 2-2
1 – #440,000 6-7 7-0 5-4 5-7 5-0 4-9 44 3-8 3-760,000 7-11 8-6 6-6 6-9 6-0 5-9 5-3 4-5 4-4
1 – #540,000 8-1 8-8 6-7 6-10 6-2 5-10 5-4 4-6 4-560,000 9-8 10-4 7-11 8-2 7-4 6-11 6-2 4-10 4-8
2 – #41 – #6
40,000 9-1 9-8 7-4 7-8 6-10 6-6 6-0 4-10 4-860,000 DR DR DR DR DR DR DR DR DR
Center distance A11,12 1-8 1-11 1-1 1-3 1-0 0-11 0-9 0-6 0-6
16
Span without stirrups9,10 4-7 5-0 3-11 4-0 3-8 3-7 3-4 3-1 3-0
1 – #440,000 6-8 7-3 5-6 5-9 5-2 4-11 4-6 3-10 3-860,000 9-3 10-1 7-9 8-0 7-2 6-10 6-3 5-4 5-2
1 – #540,000 9-6 10-4 7-10 8-2 7-4 6-11 6-5 5-5 5-360,000 11-5 12-5 9-6 9-10 8-10 8-4 7-9 6-6 6-4
2 – #41 – #6
40,000 10-7 11-7 8-10 9-2 8-3 7-9 7-2 6-1 5-1160,000 12-9 13-10 10-7 11-0 9-10 9-4 8-7 6-9 6-6
2 – #540,000 13-0 14-1 10-9 11-2 9-11 9-2 8-2 6-6 6-360,000 DR DR DR DR DR 0-6 DR DR DR
Center distance A11,12 2-3 2-8 1-7 1-8 1-4 1-3 1-0 0-9 0-8
20
Span without stirrups9,10 5-9 6-5 5-0 5-2 4-9 4-7 4-4 3-11 3-11
1 – #440,000 7-5 8-2 6-3 6-6 5-10 5-7 5-1 4-4 4-260,000 9-0 10-0 7-8 7-11 7-1 6-9 6-3 5-3 5-1
1 – #540,000 9-2 10-2 7-9 8-1 7-3 6-11 6-4 5-4 5-260,000 12-9 14-2 10-10 11-3 10-1 9-7 8-10 7-5 7-3
2 – #41 – #6
40,000 11-10 13-2 10-1 10-5 9-4 8-11 8-2 6-11 6-960,000 14-4 15-10 12-1 12-7 11-3 10-9 9-11 8-4 8-1
2 – #540,000 14-7 16-2 12-4 12-9 11-4 10-6 9-5 7-7 7-360,000 17-5 19-3 14-9 15-3 13-5 12-4 11-0 8-8 8-4
2 – #640,000 16-4 18-11 12-7 13-3 11-4 10-6 9-5 7-7 7-360,000 DR DR DR DR DR DR DR DR DR
Center distance A11,12 2-9 3-5 2-0 2-2 1-9 1-7 1-4 0-11 0-11
24
Span without stirrups9,10 6-11 7-9 6-1 6-3 5-9 5-7 5-3 4-9 4-8
1 – #440,000 8-0 9-0 6-11 7-2 6-5 6-2 5-8 4-9 4-860,000 9-9 11-0 8-5 8-9 7-10 7-6 6-11 5-10 5-8
1 – #540,000 10-0 11-3 8-7 8-11 8-0 7-7 7-0 5-11 5-960,000 13-11 15-8 12-0 12-5 11-2 10-7 9-10 8-3 8-0
2 – #41 – #6
40,000 12-11 14-6 11-2 11-6 10-5 9-10 9-1 7-8 7-560,000 15-7 17-7 13-6 13-11 12-7 11-11 11-0 9-3 9-0
2 – #540,000 15-11 17-11 13-9 14-3 12-8 11-9 10-8 8-7 8-460,000 19-1 21-6 16-5 17-1 15-1 14-0 12-6 9-11 9-7
2 – #640,000 17-7 21-1 14-1 14-10 12-8 11-9 10-8 8-7 8-460,000 DR DR DR DR DR DR DR DR DR
Center distance A11,12 3-3 4-1 2-5 2-7 2-1 1-11 1-7 1-2 1-1
Maximum clear span of lintel (ft-inches)
For SI: 1 inch = 25.4 mm; 1 psf = 0.0479 kN/m2; 1 ft = 0.3048 m; Grade 40 = 280 MPa; Grade 60 = 420 MPaSee page 7-7 for notes.
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7-7
Chapter 7 – Requirements for Lintels and Reinforcement Around Openings
Notes for Tables 7.3 through 7.101 See Table 2.1 for tolerances permitted from nominal thickness.2 Table values are based on concrete with a minimum specified compressive strength of 2,500 psi (17.2 MPa). See note 10.3 Table values are based on uniform loading. See Section 7.2 for lintels supporting concentrated loads. 4 Deflection criterion is L/240, where L is the clear span of the lintel in inches, or 1⁄2-inch (13 mm), whichever is less.5 Linear interpolation is permitted between ground snow loads and between lintel depths.6 DR indicates design required 7 Lintel depth, D, is permitted to include the available height of wall located directly above the lintel, provided that the increased lintel depth
spans the entire length of the lintel.8 Stirrups shall be fabricated from reinforcing bars with the same yield strength as that used for the main longitudinal reinforcement.9 Allowable clear span without stirrups applicable to all lintels of the same depth, D. Top and bottom reinforcement for lintels without stirrups
shall not be less than the least amount of reinforcement required for a lintel of the same depth and loading condition with stirrups. All otherspans require stirrups spaced at not more than d/2.
10 Where concrete with a minimum specified compressive strength of 3,000 psi (20.7 MPa) is used, clear spans for lintels without stirrups shall bepermitted to be multiplied by 1.05. If the increased span exceeds the allowable clear span for a lintel of the same depth and loading conditionwith stirrups, the top and bottom reinforcement shall be equal to or greater than that required for a lintel of the same depth and loading condi-tion that has an allowable clear span that is equal to or greater than that of the lintel without stirrups that has been increased.
11 Center distance, A, is the center portion of the clear span where stirrups are not required. This is applicable to all longitudinal bar sizes and steelyield strengths.
12 Where concrete with a minimum specified compressive strength of 3,000 psi (20.7 MPa) is used, center distance, A, shall be permitted to be multi-plied by 1.10.
13 The maximum clear opening width between two solid wall segments shall be 18 feet (5.5 m). See Section 5.2.1. Lintel clear spans in table greaterthan 18 feet are shown for interpolation and information purposes only.
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Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
7-8
Table 7.4. Maximum Allowable Clear Spans for 4-inch Nominal Thick Flat Lintels in Load-Bearing Walls1,2,3,4,5,6,13
Roof Clear Span 32 feet and Floor Clear Span 24 feet
LintelDepth7, D
(in.)
Number of barsand bar sizein top and
bottom of lintel
Steel yieldstrength8,
fy (psi)
Loading condition determined from Table 7.2
12 3 4 5
Maximum ground snow load (psf)30 70 30 70 30 70 30 70
8
Span without stirrups9,10 3-9 3-11 2-8 2-10 2-6 2-3 2-1 2-0 2-0
1 – #440,000 5-10 6-0 4-7 4-9 4-3 4-0 3-8 3-1 3-0
60,000 7-0 7-2 5-5 5-8 5-1 4-9 4-3 3-4 3-2
1 – #540,000 7-1 7-3 5-6 5-9 5-2 4-10 4-3 3-4 3-2
60,000 DR DR DR DR DR DR DR DR DR
Center distance A11,12 1-5 1-6 0-10 0-11 0-9 0-8 0-6 0-5 0-4
12
Span without stirrups9,10 3-10 4-1 3-1 3-2 2-10 2-9 2-7 2-4 2-3
1 – #440,000 7-5 7-10 6-0 6-3 5-6 5-2 4-9 4-0 3-11
60,000 9-0 9-6 7-3 7-6 6-8 6-3 5-9 4-10 4-9
1 – #540,000 9-2 9-8 7-4 7-8 6-10 6-5 5-10 4-11 4-10
60,000 10-11 11-6 8-9 9-2 8-2 7-8 7-0 5-6 5-3
2 – #41 – #6
40,000 10-2 10-9 8-2 8-6 7-7 7-2 6-7 5-6 5-3
60,000 12-1 12-9 9-9 10-2 8-11 8-0 7-1 5-6 5-3
Center distance A11,12 2-2 2-5 1-5 1-6 1-2 1-1 0-11 0-8 0-7
16
Span without stirrups9,10 5-2 5-8 4-3 4-5 4-0 3-10 3-7 3-3 3-2
1 – #440,000 7-6 8-1 6-2 6-5 5-9 5-4 4-11 4-2 4-1
60,000 10-5 11-3 8-7 8-11 8-0 7-6 6-11 5-10 5-8
1 – #540,000 10-7 11-5 8-9 9-1 8-2 7-7 7-0 5-11 5-9
60,000 12-9 13-10 10-7 11-0 9-10 9-2 8-6 7-2 6-11
2 – #41 – #6
40,000 11-11 12-10 9-10 10-3 9-1 8-6 7-10 6-8 6-5
60,000 14-3 15-5 11-9 12-3 10-11 10-3 9-5 7-8 7-4
2 – #540,000 14-6 15-8 12-0 12-6 11-2 10-5 9-4 7-4 7-0
60,000 DR DR DR DR DR DR DR DR DRCenter distance A11,12 2-10 3-4 1-11 2-1 1-8 1-6 1-3 0-11 0-10
20
Span without stirrups9,10 6-5 7-2 5-6 5-8 5-2 4-10 4-7 4-2 4-1
1 – #440,000 8-3 9-1 7-0 7-3 6-6 6-1 5-7 4-9 4-7
60,000 10-1 11-1 8-6 8-10 7-11 7-5 6-10 5-9 5-7
1 – #540,000 10-3 11-4 8-8 9-0 8-1 7-7 7-0 5-11 5-9
60,000 14-3 15-8 12-0 12-6 11-2 10-6 9-8 8-2 7-11
2 – #41 – #6
40,000 13-3 14-7 11-2 11-8 10-5 9-9 9-0 7-7 7-4
60,000 15-11 17-7 13-6 14-0 12-6 11-9 10-10 9-2 8-11
2 – #540,000 16-3 17-11 13-9 14-3 12-9 11-12 10-8 8-6 8-2
60,000 19-4 21-4 16-5 17-1 15-3 14-3 12-7 9-10 9-5
2 – #640,000 19-0 21-0 14-10 15-10 13-3 12-0 10-8 8-6 8-2
60,000 DR DR DR DR DR DR DR DR DR
Center distance A11,12 3-5 4-2 2-6 2-8 2-2 1-10 1-7 1-2 1-1
24
Span without stirrups9,10 7-8 8-9 6-8 6-11 6-3 5-11 5-7 5-1 5-0
1 – #440,000 8-11 10-0 7-8 8-0 7-2 6-9 6-2 5-3 5-1
60,000 10-10 12-2 9-5 9-9 8-9 8-2 7-7 6-5 6-2
1 – #540,000 11-1 12-5 9-7 10-0 8-11 8-4 7-8 6-6 6-4
60,000 15-5 17-4 13-4 13-11 12-5 11-8 10-9 9-1 8-10
2 – #41 – #6
40,000 14-3 16-1 12-5 12-11 11-6 10-9 9-11 8-5 8-2
60,000 17-3 19-5 15-0 15-7 13-11 13-1 12-0 10-2 9-11
2 – #540,000 17-7 19-10 15-3 15-10 14-2 13-4 12-0 9-7 9-3
60,000 21-2 23-9 18-4 19-0 17-0 15-11 14-3 11-3 10-9
2 – #640,000 20-9 23-4 16-6 17-7 14-9 13-5 12-0 9-7 9-3
60,000 DR DR DR DR DR DR DR DR DR
Center distance A11,12 4-0 5-1 3-0 3-3 2-7 2-3 1-11 1-5 1-4
Maximum clear span of lintel (ft–inches)
For SI: 1 inch = 25.4 mm; 1 psf = 0.0479 kN/m2; 1 ft = 0.3048 m; Grade 40 = 280 MPa; Grade 60 = 420 MPaSee page 7-7 for notes.
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Chapter 7 – Requirements for Lintels and Reinforcement Around Openings
Table 7.5. Maximum Allowable Clear Spans for 6-inch Nominal Thick Flat Lintels in Load-Bearing Walls1,2,3,4,5,6,13
Roof Clear Span 40 feet and Floor Clear Span 32 feet
LintelDepth7, D
(in.)
Number of barsand bar sizein top and
bottom of lintel
Steel yieldstrength8,
fy (psi)
Loading condition determined from Table 7.2
12 3 4 5
Maximum ground snow load (psf)30 70 30 70 30 70 30 70
8
Span without stirrups9,10 4-2 4-8 3-1 3-3 2-10 2-6 2-3 2-0 2-0
1 – #440,000 5-1 5-5 4-2 4-3 3-10 3-6 3-3 2-8 2-760,000 6-2 6-7 5-0 5-2 4-8 4-2 3-11 3-3 3-2
1 – #540,000 6-3 6-8 5-1 5-3 4-9 4-3 4-0 3-3 3-260,000 7-6 8-0 6-1 6-4 5-8 5-1 4-9 3-8 3-6
2 – #41 – #6
40,000 7-0 7-6 5-8 5-11 5-3 4-9 4-5 3-8 3-660,000 DR DR DR DR DR DR DR DR DR
Center distance A11,12 1-7 1-10 1-1 1-2 0-11 0-9 0-8 0-5 0-5
12
Span without stirrups9,10 4-2 4-8 3-5 3-6 3-2 2-11 2-9 2-5 2-4
1 – #440,000 5-7 6-1 4-8 4-10 4-4 3-11 3-8 3-0 2-1160,000 7-9 8-6 6-6 6-9 6-1 5-6 5-1 4-3 4-1
1 – #540,000 7-11 8-8 6-8 6-11 6-2 5-7 5-2 4-4 4-260,000 9-7 10-6 8-0 8-4 7-6 6-9 6-3 5-2 5-1
2 – #41 – #6
40,000 8-11 9-9 7-6 7-9 6-11 6-3 5-10 4-10 4-860,000 10-8 11-9 8-12 9-4 8-4 7-6 7-0 5-10 5-8
2 – #540,000 10-11 12-0 9-2 9-6 8-6 7-8 7-2 5-6 5-360,000 12-11 14-3 10-10 11-3 10-1 9-0 8-1 6-1 5-10
2 – #640,000 12-9 14-0 10-8 11-1 9-7 8-1 7-3 5-6 5-360,000 DR DR DR DR DR DR DR DR DR
Center distance A11,12 2-6 3-0 1-9 1-10 1-6 1-3 1-1 0-9 0-8
16
Span without stirrups9,10 5-7 6-5 4-9 4-11 4-5 4-0 3-10 3-4 3-4
1 – #440,000 6-5 7-2 5-6 5-9 5-2 4-8 4-4 3-7 3-660,000 7-10 8-9 6-9 7-0 6-3 5-8 5-3 4-4 4-3
1 – #540,000 7-11 8-11 6-10 7-1 6-5 5-9 5-4 4-5 4-460,000 11-1 12-6 9-7 9-11 8-11 8-0 7-6 6-2 6-0
2 – #41 – #6
40,000 10-3 11-7 8-10 9-2 8-3 7-6 6-11 5-9 5-760,000 12-5 14-0 10-9 11-1 10-0 9-0 8-5 7-0 6-9
2 – #540,000 12-8 14-3 10-11 11-4 10-2 9-2 8-7 6-9 6-660,000 15-2 17-1 13-1 13-7 12-3 11-0 10-3 7-11 7-7
2 – #640,000 14-11 16-9 12-8 13-4 11-4 9-8 8-8 6-9 6-660.000 DR DR DR DR DR DR DR DR DR
Center distance A11,12 3-3 4-1 2-5 2-7 2-1 1-9 1-6 1-0 1-0
20
Span without stirrups9,10 6-11 8-2 6-1 6-3 5-8 5-2 4-11 4-4 4-3
1 – #540,000 8-9 10-1 7-9 8-0 7-3 6-6 6-1 5-1 4-1160,000 10-8 12-3 9-5 9-9 8-10 8-0 7-5 6-2 6-0
2 – #41 – #6
40,000 9-11 11-4 8-9 9-1 8-2 7-4 6-10 5-8 5-760,000 13-9 15-10 12-2 12-8 11-5 10-3 9-7 7-11 7-9
2 – #540,000 14-0 16-2 12-5 12-11 11-7 10-6 9-9 7-11 7-860,000 16-11 19-6 15-0 15-6 14-0 12-7 11-9 9-1 8-9
2 – #640,000 16-7 19-1 14-7 15-3 13-1 11-3 10-2 7-11 7-860,000 19-11 22-10 17-4 18-3 15-6 13-2 11-10 9-1 8-9
Center distance A11,12 3-11 5-2 3-1 3-3 2-8 2-2 1-11 1-4 1-3
24
Span without stirrups9,10 8-2 9-10 7-4 7-8 6-11 6-4 5-11 5-3 5-2
1 – #540,000 9-5 11-1 8-7 8-10 8-0 7-3 6-9 5-7 5-560,000 11-6 13-6 10-5 10-9 9-9 8-9 8-2 6-10 6-8
2 – #41 – #6
40,000 10-8 12-6 9-8 10-0 9-0 8-2 7-7 6-4 6-260,000 12-11 15-2 11-9 12-2 11-0 9-11 9-3 7-8 7-6
2 – #540,000 15-2 17-9 13-9 14-3 12-10 11-7 10-10 9-0 8-960,000 18-4 21-6 16-7 17-3 15-6 14-0 13-1 10-4 10-0
2 – #640,000 18-0 21-1 16-4 16-11 14-10 12-9 11-8 9-2 8-1160,000 21-7 25-4 19-2 20-4 17-2 14-9 13-4 10-4 10-0
Center distance A11,12 4-6 6-2 3-8 4-0 3-3 2-8 2-3 1-7 1-6
For SI: 1 inch = 25.4 mm; 1 psf = 0.0479 kN/m2; 1 ft = 0.3048 m; Grade 40 = 280 MPa; Grade 60 = 420 MPaSee Page 7-7 for notes.
Maximum clear span of lintel (ft–inches)
O85573 1.qxd:FPO 85573 1 1/24/08 10:58 AM Page 7-9
Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
7-10
Table 7.6. Maximum Allowable Clear Spans for 6-inch Nominal Thick Flat Lintels in Load-Bearing Walls1,2,3,4,5,6,13
Roof Clear Span 32 feet and Floor Clear Span 24 feet
LintelDepth7, D
(in.)
Number of barsand bar sizein top and
bottom of lintel
Steel yieldstrength8,
fy (psi)
Loading condition determined from Table 7.2
12 3 4 5
Maximum ground snow load (psf)30 70 30 70 30 70 30 70
8
Span without stirrups9,10 5-1 5-6 3-8 3-10 3-3 2-9 2-6 2-0 2-0
1 – #440,000 5-9 6-1 4-7 4-10 4-3 3-9 3-6 2-11 2-1060,000 6-11 7-4 5-7 5-9 5-2 4-6 4-3 3-6 3-5
1 – #540,000 7-0 7-5 5-8 5-11 5-3 4-8 4-4 3-7 3-660,000 8-5 8-11 6-9 7-1 6-3 5-6 5-2 4-1 3-11
2 – #41 – #6
40,000 7-10 8-4 6-4 6-7 5-10 5-2 4-10 4-0 3-1060,000 DR DR DR DR DR DR DR DR DR
Center distance A11,12 2-0 2-3 1-4 1-5 1-2 0-11 0-9 0-6 0-6
12
Span without stirrups9,10 4-9 5-4 3-10 4-0 3-6 3-1 2-11 2-6 2-6
1 – #440,000 6-3 6-9 5-2 5-5 4-10 4-3 4-0 3-3 3-260,000 8-8 9-6 7-3 7-7 6-9 5-11 5-6 4-7 4-6
1 – #540,000 8-10 9-8 7-5 7-8 6-11 6-1 5-8 4-8 4-660,000 10-8 11-8 8-11 9-4 8-4 7-4 6-10 5-8 5-6
2 – #41 – #6
40,000 9-11 10-10 8-4 8-8 7-9 6-10 6-4 5-3 5-160,000 11-11 13-0 10-0 10-5 9-3 8-2 7-7 6-3 6-2
2 – #540,000 12-2 13-3 10-2 10-7 9-6 8-4 7-9 6-2 5-1160,000 14-5 15-9 12-1 12-7 11-3 9-11 9-2 6-10 6-7
2 – #640,000 14-3 15-6 11-11 12-4 11-1 9-3 8-3 6-2 5-1160,000 DR DR DR DR DR DR DR DR DR
Center distance A11,12 3-1 3-8 2-2 2-4 1-10 1-5 1-3 0-10 0-10
16
Span without stirrups9,10 6-4 7-4 5-4 5-7 4-11 4-4 4-1 3-6 3-6
1 – #440,000 7-1 8-0 6-2 6-5 5-9 5-0 4-8 3-11 3-960,000 8-8 9-9 7-6 7-9 7-0 6-2 5-9 4-9 4-7
1 – #540,000 8-10 9-11 7-8 7-11 7-1 6-3 5-10 4-10 4-860,000 12-3 13-10 10-8 11-1 9-11 8-9 8-1 6-9 6-7
2 – #41 – #6
40,000 11-5 12-10 9-10 10-3 9-2 8-1 7-6 6-3 6-160,000 13-9 15-6 11-11 12-5 11-1 9-9 9-1 7-6 7-4
2 – #540,000 14-0 15-9 12-2 12-8 11-4 10-0 9-3 7-6 7-360,000 16-10 18-11 14-7 15-2 13-7 12-0 11-2 8-10 8-6
2 – #640,000 16-6 18-7 14-4 14-11 13-4 11-0 9-10 7-6 7-360.000 DR DR DR DR DR DR DR DR DR
Center distance A11,12 4-0 5-0 3-0 3-3 2-7 2-0 1-9 1-2 1-2
20
Span without stirrups9,10 7-9 9-4 6-9 7-1 6-3 5-7 5-3 4-6 4-5
1 – #540,000 9-8 11-2 8-7 9-0 8-0 7-1 6-7 5-6 5-460,000 11-9 13-7 10-6 10-11 9-9 8-8 8-0 6-8 6-6
2 – #41 – #6
40,000 10-10 12-7 9-9 10-1 9-1 8-0 7-5 6-2 6-060,000 15-2 17-6 13-6 14-1 12-7 11-2 10-4 8-7 8-5
2 – #540,000 15-5 17-10 13-10 14-4 12-10 11-4 10-7 8-9 8-660,000 18-7 21-6 16-8 17-4 15-6 13-8 12-9 10-2 9-10
2 – #640,000 18-3 21-1 16-4 17-0 15-3 12-8 11-5 8-9 8-660,000 21-10 24-10 19-6 20-4 18-2 15-0 13-5 10-2 9-10
Center distance A11,12 4-9 6-4 3-9 4-1 3-3 2-7 2-3 1-6 1-5
24
Span without stirrups9,10 9-0 11-2 8-3 8-7 7-7 6-9 6-4 5-6 5-5
1 – #540,000 10-3 12-2 9-6 9-10 8-10 7-10 7-3 6-0 5-1160,000 12-7 14-10 11-7 12-0 10-9 9-6 8-10 7-4 7-2
2 – #41 – #6
40,000 11-7 13-9 10-8 11-1 10-0 8-10 8-3 6-10 6-860,000 14-2 16-9 13-0 13-6 12-2 10-9 10-0 8-4 8-1
2 – #540,000 16-7 19-7 15-3 15-10 14-3 12-7 11-8 9-9 9-660,000 20-0 23-8 18-5 19-2 17-2 15-2 14-2 11-6 11-1
2 – #640,000 19-8 23-3 18-1 18-9 16-10 14-5 13-0 10-1 9-960,000 23-7 22-10 21-9 22-7 20-3 16-8 15-0 11-6 11-1
Center distance A11,12 5-4 7-6 4-7 4-11 4-0 3-1 2-8 1-10 1-9
For SI: 1 inch = 25.4 mm; 1 psf = 0.0479 kN/m2; 1 ft = 0.3048 m; Grade 40 = 280 MPa; Grade 60 = 420 MPaSee Page 7-7 for notes.
Maximum clear span of lintel (ft–inches)
O85573 1.qxd:FPO 85573 1 1/24/08 10:58 AM Page 7-10
7-11
Chapter 7 – Requirements for Lintels and Reinforcement Around Openings
Table 7.7. Maximum Allowable Clear Spans for 8-inch Nominal Thick Flat Lintels in Load-Bearing Walls1,2,3,4,5,6,13
Roof Clear Span 40 feet and Floor Clear Span 32 feet
LintelDepth7, D
(in.)
Number of barsand bar sizein top and
bottom of lintel
Steel yieldstrength8,
fy (psi)
Loading condition determined from Table 7.2
12 3 4 5
Maximum ground snow load (psf)30 70 30 70 30 70 30 70
8
Span without stirrups9,10 4-4 4-9 3-7 3-9 3-4 2-10 2-7 2-1 2-0
1 – #440,000 4-4 4-9 3-7 3-9 3-4 2-11 2-9 2-3 2-260,000 6-1 6-7 5-0 5-3 4-8 4-0 3-9 3-1 3-0
1 – #540,000 6-2 6-9 5-2 5-4 4-9 4-1 3-10 3-2 3-160,000 7-5 8-1 6-2 6-5 5-9 4-11 4-7 3-9 3-8
2 – #41 – #6
40,000 6-11 7-6 5-9 6-0 5-4 4-7 4-4 3-6 3-560,000 8-3 9-0 6-11 7-2 6-5 5-6 5-2 4-2 4-1
2 – #540,000 8-5 9-2 7-0 7-3 6-6 5-7 5-3 4-2 4-060,000 DR DR DR DR DR DR DR DR DR
Center distance A11,12 2-1 2-6 1-5 1-6 1-3 0-11 0-10 0-6 0-6
12
Span without stirrups9,10 4-10 5-8 4-0 4-2 3-9 3-2 3-0 2-7 2-6
1 – #440,000 5-5 6-1 4-8 4-10 4-4 3-9 3-6 2-10 2-1060,000 6-7 7-5 5-8 5-11 5-4 4-7 4-3 3-6 3-5
1 – #540,000 6-9 7-7 5-9 6-0 5-5 4-8 4-4 3-7 3-660,000 9-4 10-6 8-1 8-4 7-6 6-6 6-1 5-0 4-10
2 – #41 – #6
40,000 8-8 9-9 7-6 7-9 7-0 6-0 5-8 4-7 4-660,000 10-6 11-9 9-1 9-5 8-5 7-3 6-10 5-7 5-5
2 – #540,000 10-8 12-0 9-3 9-7 8-7 7-5 6-11 5-6 5-460,000 12-10 14-5 11-1 11-6 10-4 8-11 8-4 6-7 6-4
2 – #640,000 12-7 14-2 10-10 11-3 10-2 8-3 7-6 5-6 5-460,000 DR DR DR DR DR DR DR DR DR
Center distance A11,12 3-2 4-0 2-4 2-6 2-0 1-6 1-4 0-11 0-10
16
Span without stirrups9,10 6-5 7-9 5-7 5-10 5-2 4-5 4-2 3-7 3-6
1 – #440,000 6-2 7-1 5-6 5-8 5-1 4-5 4-2 3-5 3-460,000 7-6 8-8 6-8 6-11 6-3 5-5 5-1 4-2 4-0
1 – #540,000 7-8 8-10 6-10 7-1 6-4 5-6 5-2 4-3 4-160,000 9-4 10-9 8-4 8-7 7-9 6-8 6-3 5-2 5-0
2 – #41 – #6
40,000 8-8 10-0 7-8 8-0 7-2 6-2 5-10 4-9 4-860,000 12-0 13-11 10-9 11-2 10-0 8-8 8-1 6-8 6-6
2 – #540,000 12-3 14-2 11-0 11-4 10-3 8-10 8-3 6-9 6-760,000 14-10 17-2 13-3 13-8 12-4 10-8 10-0 7-11 7-8
2 – #640,000 14-6 16-10 13-0 13-5 12-1 10-1 9-2 6-11 6-860.000 17-5 20-2 15-7 16-1 14-6 11-10 10-8 7-11 7-8
Center distance A11,12 4-1 5-5 3-3 3-6 2-10 2-1 1-10 1-3 1-2
20
Span without stirrups9,10 7-10 9-10 7-1 7-5 6-7 5-8 5-4 4-7 4-6
1 – #540,000 8-4 9-11 7-8 8-0 7-2 6-3 5-10 4-9 4-860,000 10-2 12-1 9-5 9-9 8-9 7-7 7-1 5-10 5-8
2 – #41 – #6
40,000 9-5 11-3 8-8 9-0 8-1 7-0 6-7 5-5 5-360,000 11-6 13-8 10-7 11-0 9-11 8-7 8-0 6-7 6-5
2 – #540,000 11-9 13-11 10-10 11-2 10-1 8-9 8-2 6-8 6-760,000 16-4 19-5 15-0 15-7 14-0 12-2 11-4 9-3 9-0
2 – #640,000 16-0 19-0 14-9 15-3 13-9 11-10 10-10 8-3 8-060,000 19-3 22-11 17-9 18-5 16-7 13-7 12-4 9-3 9-0
Center distance A11,12 4-10 6-10 4-1 4-5 3-7 2-8 2-4 1-7 1-6
24
Span without stirrups9,10 9-2 11-9 8-7 8-11 8-0 6-11 6-6 5-7 5-6
1 – #540,000 8-11 10-10 8-6 8-9 7-11 6-10 6-5 5-3 5-260,000 10-11 13-3 10-4 10-8 9-8 8-4 7-10 6-5 6-3
2 – #41 – #6
40,000 10-1 12-3 9-7 9-11 8-11 7-9 7-3 6-0 5-1060,000 12-3 15-0 11-8 12-1 10-11 9-5 8-10 7-3 7-1
2 – #540,000 12-6 15-3 11-11 12-4 11-1 9-7 9-0 7-5 7-360,000 17-6 21-3 16-7 17-2 15-6 13-5 12-7 10-4 10-1
2 – #640,000 17-2 20-11 16-3 16-10 15-3 13-2 12-4 9-7 9-460,000 20-9 25-3 19-8 20-4 18-5 15-4 14-0 10-7 10-3
Center distance A11,12 5-6 8-1 4-11 5-3 4-4 3-3 2-10 1-11 1-10
For SI: 1 inch = 25.4 mm; 1 psf = 0.0479 kN/m2; 1 ft = 0.3048 m; Grade 40 = 280 MPa; Grade 60 = 420 MPaTop and bottom reinforcement for lintels without stirrups shown in shaded cells shall be equal to or greater than that required for a lintel of thesame depth and loading condition that has an allowable clear span that is equal to or greater than that of the lintel without stirrups. See Page 7-7 for additional notes.
Maximum clear span of lintel (ft–inches)
O85573 1.qxd:FPO 85573 1 1/24/08 10:58 AM Page 7-11
Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
7-12
Table 7.8. Maximum Allowable Clear Spans for 8-inch Nominal Thick Flat Lintels in Load-Bearing Walls1,2,3,4,5,6,13
Roof Clear Span 32 feet and Floor Clear Span 24 feet
LintelDepth7, D
(in.)
Number of barsand bar sizein top and
bottom of lintel
Steel yieldstrength8,
fy (psi)
Loading condition determined from Table 7.2
12 3 4 5
Maximum ground snow load (psf)30 70 30 70 30 70 30 70
8
Span without stirrups9,10 6-2 7-1 4-7 4-10 4-1 3-2 2-10 2-3 2-2
1 – #440,000 4-10 5-3 4-0 4-2 3-9 3-1 2-11 2-4 2-460,000 6-9 7-4 5-7 5-10 5-3 4-4 4-1 3-4 3-3
1 – #540,000 6-11 7-6 5-9 5-11 5-4 4-5 4-2 3-4 3-360,000 8-4 9-0 6-10 7-2 6-5 5-4 5-0 4-1 4-0
2 – #41 – #6
40,000 7-9 8-4 6-5 6-8 5-11 4-11 4-8 3-9 3-860,000 9-3 10-0 7-8 8-0 7-1 5-11 5-7 4-6 4-5
2 – #540,000 9-5 10-2 7-9 8-1 7-3 6-0 5-8 4-7 4-660,000 DR DR DR DR DR DR DR DR DR
Center distance A11,12 2-7 3-0 1-9 1-11 1-6 1-1 0-11 0-7 0-7
12
Span without stirrups9,10 5-6 6-7 4-7 4-10 4-2 3-5 3-3 2-8 2-8
1 – #440,000 6-0 6-9 5-2 5-5 4-10 4-0 3-9 3-1 3-060,000 7-3 8-2 6-4 6-7 5-10 4-11 4-7 3-9 3-8
1 – #540,000 7-5 8-4 6-5 6-8 6-0 5-0 4-8 3-10 3-960,000 10-4 11-8 9-0 9-4 8-4 7-0 6-6 5-4 5-3
2 – #41 – #6
40,000 9-7 10-10 8-4 8-8 7-9 6-6 6-1 4-11 4-1060,000 11-7 13-1 10-1 10-6 9-4 7-10 7-4 6-0 5-10
2 – #540,000 11-10 13-4 10-3 10-8 9-6 8-0 7-6 6-1 5-1160,000 14-2 15-11 12-3 12-9 11-5 9-7 8-11 7-3 7-1
2 – #640,000 13-11 15-8 12-1 12-7 11-3 9-4 8-5 6-2 5-1160,000 DR DR DR DR DR DR DR DR DR
Center distance A11,12 3-10 4-11 2-11 3-2 2-6 1-9 1-6 1-0 1-0
16
Span without stirrups9,10 7-3 8-11 6-4 6-8 5-9 4-9 4-6 3-9 3-8
1 – #440,000 6-9 7-10 6-1 6-4 5-8 4-9 4-5 3-8 3-760,000 8-3 9-7 7-5 7-9 6-11 5-10 5-5 4-5 4-4
1 – #540,000 8-5 9-9 7-7 7-11 7-1 5-11 5-7 4-6 4-560,000 10-3 11-11 9-3 9-7 8-7 7-3 6-9 5-6 5-5
2 – #41 – #6
40,000 9-6 11-0 8-7 8-11 8-0 6-8 6-3 5-1 5-060,000 13-2 15-5 11-11 12-5 11-1 9-4 8-9 7-1 7-0
2 – #540,000 13-6 15-8 12-2 12-8 11-4 9-6 8-11 7-3 7-160,000 16-3 18-11 14-8 15-3 13-8 11-5 10-9 8-9 8-6
2 – #640,000 15-11 18-7 14-5 15-0 13-5 11-3 10-3 7-7 7-460.000 19-1 22-0 17-3 17-11 16-1 13-4 12-0 8-9 8-6
Center distance A11,12 4-11 6-7 4-0 4-4 3-6 2-5 2-2 1-5 1-4
20
Span without stirrups9,10 8-9 11-3 8-0 8-5 7-4 6-1 5-9 4-10 4-9
1 – #540,000 9-1 10-11 8-6 8-10 8-0 6-8 6-3 5-1 5-060,000 11-1 13-4 10-5 10-10 9-9 8-2 7-8 6-3 6-1
2 – #41 – #6
40,000 10-3 12-4 9-8 10-0 9-0 7-6 7-1 5-9 5-860,000 12-6 15-0 11-9 12-2 10-11 9-2 8-7 7-1 6-11
2 – #540,000 12-9 15-4 12-0 12-5 11-2 9-4 8-10 7-2 7-060,000 17-9 21-4 16-8 17-3 15-6 13-0 12-3 10-0 9-9
2 – #640,000 17-5 20-11 16-4 17-0 15-3 12-9 12-0 9-0 8-960,000 21-0 25-3 19-8 20-5 18-4 15-3 13-10 10-3 9-11
Center distance A11,12 5-9 8-3 5-0 5-5 4-4 3-1 2-9 1-10 1-9
24
Span without stirrups9,10 10-1 13-5 9-8 10-2 8-11 7-5 6-11 5-10 5-9
1 – #540,000 9-8 11-11 9-4 9-9 8-9 7-4 6-11 5-8 5-660,000 11-9 14-7 11-5 11-10 10-8 9-0 8-5 6-11 6-9
2 – #41 – #6
40,000 10-11 13-6 10-7 11-0 9-10 8-4 7-10 6-5 6-360,000 13-4 16-5 12-11 13-5 12-0 10-2 9-6 7-9 7-7
2 – #540,000 13-7 16-9 13-2 13-8 12-3 10-4 9-8 7-11 7-960,000 18-11 23-4 18-4 19-0 17-2 14-5 13-6 11-1 10-10
2 – #640,000 18-7 22-11 18-0 18-8 16-10 14-2 13-3 10-6 10-260,000 22-5 27-8 21-9 22-7 20-4 17-1 15-8 11-8 11-4
Center distance A11,12 6-5 9-9 6-0 6-6 5-3 3-9 3-3 2-2 2-1
For SI: 1 inch = 25.4 mm; 1 psf = 0.0479 kN/m2; 1 ft = 0.3048 m; Grade 40 = 280 MPa; Grade 60 = 420 MPaTop and bottom reinforcement for lintels without stirrups shown in shaded cells shall be equal to or greater than that required for a lintel of the
same depth and loading condition that has an allowable clear span that is equal to or greater than that of the lintel without stirrups.See Page 7-7 for additional notes.
Maximum clear span of lintel (ft–inches)
O85573 1.qxd:FPO 85573 1 1/24/08 10:58 AM Page 7-12
7-13
Chapter 7 – Requirements for Lintels and Reinforcement Around Openings
Table 7.9. Maximum Allowable Clear Spans for 10-inch Nominal Thick Flat Lintels in Load-Bearing Walls1,2,3,4,5,6,13
Roof Clear Span 40 feet and Floor Clear Span 32 feet
LintelDepth7, D
(in.)
Number of barsand bar sizein top and
bottom of lintel
Steel yieldstrength8,
fy (psi)
Loading condition determined from Table 7.2
1
2 3 4 5Maximum ground snow load (psf)
30 70 30 70 30 70 30 70
8
Span without stirrups9,10 6-0 7-2 4-7 4-10 4-1 3-1 2-11 2-3 2-2
1 – #440,000 4-3 4-9 3-7 3-9 3-4 2-9 2-7 2-1 2-160,000 5-11 6-7 5-0 5-3 4-8 3-10 3-8 2-11 2-11
1 – #540,000 6-1 6-9 5-2 5-4 4-9 3-11 3-9 3-0 2-1160,000 7-4 8-1 6-3 6-5 5-9 4-9 4-6 3-7 3-7
2 – #41 – #6
40,000 6-10 7-6 5-9 6-0 5-5 4-5 4-2 3-4 3-460,000 8-2 9-1 6-11 7-2 6-6 5-4 5-0 4-1 4-0
2 – #540,000 8-4 9-3 7-1 7-4 6-7 5-5 5-1 4-1 4-060,000 9-11 11-0 8-5 8-9 7-10 6-6 6-1 4-8 4-6
2 – #640,000 9-9 10-10 8-3 8-7 7-9 6-4 5-10 4-1 4-060,000 DR DR DR DR DR DR DR DR DR
Center distance A11,12 2-6 3-1 1-10 1-11 1-7 1-1 0-11 0-7 0-7
12
Span without stirrups9,10 5-5 6-7 4-7 4-10 4-3 3-5 3-3 2-8 2-8
1 – #440,000 5-3 6-0 4-8 4-10 4-4 3-7 3-4 2-9 2-860,000 6-5 7-4 5-8 5-10 5-3 4-4 4-1 3-4 3-3
1 – #540,000 6-6 7-6 5-9 6-0 5-5 4-5 4-2 3-5 3-460,000 7-11 9-1 7-0 7-3 6-7 5-5 5-1 4-2 4-0
2 – #41 – #6
40,000 7-4 8-5 6-6 6-9 6-1 5-0 4-9 3-10 3-960,000 10-3 11-9 9-1 9-5 8-6 7-0 6-7 5-4 5-3
2 – #540,000 10-5 12-0 9-3 9-7 8-8 7-2 6-9 5-5 5-460,000 12-7 14-5 11-2 11-6 10-5 8-7 8-1 6-6 6-4
2 – #640,000 12-4 14-2 10-11 11-4 10-2 8-5 7-8 5-7 5-560,000 14-9 17-0 13-1 13-6 12-2 10-0 9-1 6-6 6-4
Center distance A11,12 3-9 4-11 2-11 3-2 2-7 1-9 1-7 1-0 1-0
16
Span without stirrups9,10 7-1 9-0 6-4 6-8 5-10 4-9 4-6 3-9 3-8
1 – #440,000 5-11 7-0 5-5 5-8 5-1 4-3 4-0 3-3 3-260,000 7-3 8-7 6-8 6-11 6-3 5-2 4-10 3-11 3-10
1 – #540,000 7-4 8-9 6-9 7-0 6-4 5-3 4-11 4-0 3-1160,000 9-0 10-8 8-3 8-7 7-9 6-5 6-0 4-11 4-9
2 – #41 – #6
40,000 8-4 9-11 7-8 7-11 7-2 5-11 5-7 4-6 4-560,000 10-2 12-0 9-4 9-8 8-9 7-3 6-10 5-6 5-5
2 – #540,000 10-4 12-3 9-6 9-10 8-11 7-4 6-11 5-8 5-660,000 14-4 17-1 13-3 13-8 12-4 10-3 9-8 7-10 7-8
2 – #640,000 14-1 16-9 13-0 13-5 12-2 10-1 9-6 7-0 6-1060.000 17-0 20-2 15-8 16-2 14-7 12-0 10-11 8-0 7-9
Center distance A11,12 4-9 6-8 4-0 4-4 3-6 2-5 2-2 1-5 1-4
20
Span without stirrups9,10 8-7 11-4 8-1 8-5 7-5 6-1 5-9 4-10 4-9
1 – #440,000 6-5 7-10 6-2 6-4 5-9 4-9 4-6 3-8 3-760,000 7-10 9-7 7-6 7-9 7-0 5-10 5-6 4-5 4-4
1 – #540,000 8-0 9-9 7-8 7-11 7-2 5-11 5-7 4-6 4-560,000 9-9 11-11 9-4 9-8 8-9 7-3 6-10 5-6 5-5
2 – #41 – #6
40,000 9-0 11-1 8-8 8-11 8-1 6-9 6-4 5-2 5-060,000 11-0 13-6 10-6 10-11 9-10 8-2 7-9 6-3 6-2
2 – #540,000 11-3 13-9 10-9 11-1 10-0 8-4 7-10 6-5 6-360,000 15-8 19-2 15-0 15-6 14-0 11-8 11-0 8-11 8-9
2 – #640,000 15-5 18-10 14-8 15-2 13-9 11-5 10-9 8-6 8-360,000 18-7 22-9 17-9 18-5 16-7 13-10 12-9 9-5 9-2
Center distance A11,12 5-7 8-4 5-1 5-5 4-5 3-1 2-9 1-10 1-9
24
Span without stirrups9,10 9-11 13-7 9-9 10-2 9-0 7-5 7-0 5-10 5-9
1 – #540,000 8-6 10-8 8-5 8-8 7-10 6-6 6-2 5-0 4-1160,000 10-5 13-0 10-3 10-7 9-7 8-0 7-6 6-1 6-0
2 – #41 – #6
40,000 9-7 12-1 9-6 9-9 8-10 7-5 7-0 5-8 5-660,000 11-9 14-9 11-7 11-11 10-10 9-0 8-6 6-11 6-9
2 – #540,000 12-0 15-0 11-9 12-2 11-0 9-2 8-8 7-1 6-1160,000 14-7 18-3 14-4 14-10 13-5 11-2 10-7 8-7 8-5
2 – #640,000 14-3 17-11 14-1 14-7 13-2 11-0 10-4 8-5 8-360,000 19-11 25-0 19-7 20-3 18-4 15-3 14-5 10-10 10-7
Center distance A11,12 6-3 9-11 6-1 6-6 5-4 3-9 3-4 2-2 2-1
For SI: 1 inch = 25.4 mm; 1 psf = 0.0479 kN/m2; 1 ft = 0.3048 m; Grade 40 = 280 MPa; Grade 60 = 420 MPaTop and bottom reinforcement for lintels without stirrups shown in shaded cells shall be equal to or greater than that required for alintel of the same depth and loading condition that has an allowable clear span that is equal to or greater than that of the lintel without stirrups. See Page 7-7 for additional notes.
Maximum clear span of lintel (ft–inches)
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Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
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Table 7.10. Maximum Allowable Clear Spans for 10-inch Nominal Thick Flat Lintels in Load-Bearing Walls1,2,3,4,5,6,13
Roof Clear Span 32 feet and Floor Clear Span 24 feet
LintelDepth7, D
(in.)
Number of barsand bar sizein top and
bottom of lintel
Steel yieldstrength8,
fy (psi)
Loading condition determined from Table 7.2
12 3 4 5
Maximum ground snow load (psf)30 70 30 70 30 70 30 70
8
Span without stirrups9,10 7-2 8-6 5-5 5-10 4-10 3-5 3-2 2-5 2-4
1 – #440,000 4-9 5-3 4-0 4-2 3-9 3-0 2-10 2-3 2-260,000 6-7 7-4 5-7 5-10 5-3 4-2 3-11 3-2 3-1
1 – #540,000 6-9 7-5 5-9 5-11 5-4 4-3 4-0 3-2 3-260,000 8-2 9-0 6-11 7-2 6-5 5-1 4-10 3-10 3-9
2 – #41 – #6
40,000 7-7 8-4 6-5 6-8 6-0 4-9 4-6 3-7 3-660,000 9-2 10-1 7-9 8-0 7-2 5-9 5-5 4-4 4-3
2 – #540,000 9-3 10-3 7-10 8-2 7-4 5-10 5-6 4-5 4-460,000 11-1 12-2 9-4 9-9 8-9 6-11 6-6 5-2 5-0
2 – #640,000 10-10 12-0 9-3 9-7 8-7 6-10 6-5 4-7 4-560,000 DR DR DR DR DR DR DR DR DR
Center distance A11,12 3-1 3-9 2-3 2-5 1-11 1-3 1-1 0-8 0-8
12
Span without stirrups9,10 6-2 7-8 5-3 5-7 4-10 3-8 3-5 2-10 2-9
1 – #440,000 5-9 6-8 5-2 5-4 4-10 3-10 3-7 2-11 2-1060,000 7-0 8-1 6-3 6-6 5-10 4-8 4-5 3-6 3-6
1 – #540,000 7-2 8-3 6-5 6-8 6-0 4-9 4-6 3-7 3-660,000 8-9 10-1 7-10 8-1 7-3 5-10 5-6 4-5 4-4
2 – #41 – #6
40,000 8-1 9-4 7-3 7-6 6-9 5-4 5-1 4-1 4-060,000 11-3 13-0 10-1 10-6 9-5 7-6 7-1 5-8 5-7
2 – #540,000 11-6 13-3 10-3 10-8 9-7 7-7 7-2 5-9 5-860,000 13-10 16-0 12-4 12-10 11-6 9-2 8-8 7-0 6-10
2 – #640,000 13-7 15-8 12-2 12-7 11-4 9-0 8-6 6-1 5-1160,000 16-3 18-6 14-6 15-1 13-6 10-9 10-2 7-2 7-0
Center distance A11,12 4-6 6-0 3-7 3-11 3-2 2-0 1-9 1-2 1-1
16
Span without stirrups9,10 8-0 10-5 7-3 7-8 6-8 5-1 4-9 3-11 3-10
1 – #440,000 6-5 7-9 6-0 6-3 5-8 4-6 4-3 3-5 3-460,000 7-10 9-5 7-4 7-8 6-11 5-6 5-2 4-2 4-1
1 – #540,000 8-0 9-8 7-6 7-10 7-0 5-7 5-4 4-3 4-260,000 9-9 11-9 9-2 9-6 8-7 6-10 6-6 5-3 5-1
2 – #41 – #6
40,000 9-1 10-10 8-6 8-10 7-11 6-4 6-0 4-10 4-960,000 11-0 13-3 10-4 10-9 9-8 7-9 7-3 5-10 5-9
2 – #540,000 11-3 13-6 10-7 10-11 9-10 7-11 7-5 6-0 5-1160,000 15-8 18-9 14-8 15-3 13-8 10-11 10-4 8-4 8-2
2 – #640,000 15-4 18-5 14-5 14-11 13-5 10-9 10-2 7-8 7-660.000 18-6 22-2 17-4 18-0 16-2 12-11 12-2 8-9 8-6
Center distance A11,12 5-7 8-1 4-11 5-4 4-4 2-9 2-5 1-7 1-6
20
Span without stirrups9,10 9-6 13-0 9-3 9-8 8-5 6-6 6-1 5-0 5-0
1 – #440,000 6-11 8-7 6-9 7-0 6-4 5-1 4-10 3-11 3-1060,000 8-6 10-3 8-3 8-7 7-9 6-3 5-10 4-9 4-8
1 – #540,000 8-8 10-9 8-5 8-9 7-11 6-4 6-0 4-10 4-960,000 10-7 13-1 10-4 10-8 9-8 7-9 7-4 5-11 5-9
2 – #41 – #6
40,000 9-9 12-2 9-6 9-11 8-11 7-2 6-9 5-6 5-460,000 11-11 14-9 11-8 12-1 10-10 8-9 8-3 6-8 6-6
2 – #540,000 12-2 15-1 11-10 12-4 11-1 8-11 8-5 6-9 6-860,000 16-11 21-1 16-7 17-2 15-6 12-5 11-9 9-6 9-4
2 – #640,000 16-7 20-8 16-3 16-10 15-2 12-2 11-6 9-3 9-060,000 20-1 25-0 19-8 20-4 18-4 14-9 13-11 10-3 10-0
Center distance A11,12 6-6 10-0 6-3 6-8 5-5 3-6 3-1 2-0 2-0
24
Span without stirrups9,10 10-11 15-6 11-1 11-8 10-2 7-11 7-5 6-2 6-0
1 – #540,000 9-1 11-8 9-3 9-7 8-8 7-0 6-7 5-4 5-360,000 11-2 14-3 11-3 11-8 10-7 8-6 8-0 6-6 6-5
2 – #41 – #6
40,000 10-4 13-2 10-5 10-10 9-9 7-10 7-5 6-0 5-1160,000 12-7 16-1 12-9 13-3 11-11 9-7 9-1 7-4 7-3
2 – #540,000 12-10 16-5 13-0 13-6 12-2 9-10 9-3 7-6 7-460,000 15-8 20-0 15-10 16-5 14-10 11-11 11-3 9-2 9-0
2 – #640,000 15-4 19-7 15-6 16-1 14-6 11-9 11-1 9-0 8-960,000 21-4 27-4 21-7 22-5 20-3 16-4 15-5 11-10 11-6
Center distance A11,12 7-3 11-10 7-5 8-0 6-6 4-3 3-9 2-6 2-5
For SI: 1 inch = 25.4 mm; 1 psf = 0.0479 kN/m2; 1 ft = 0.3048 m; Grade 40 = 280 MPa; Grade 60 = 420 MPaTop and bottom reinforcement for lintels without stirrups shown in shaded cells shall be equal to or greater than that required fora lintel of the same depth and loading condition that has an allowable clear span that is equal to or greater than that of the lintel withoutstirrups. See Page 7-7 for additional notes.
Maximum clear span of lintel (ft–inches)
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Chapter 7 – Requirements for Lintels and Reinforcement Around Openings
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Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
7-16
Table 7.11. Maximum Allowable Clear Spans for 6-inch Thick Waffle-Grid Lintels in Load-Bearing Walls1,2,3,4,5,6,15
Maximum Roof Clear Span of 40 feet and Maximum Floor Clear Span of 32 feet
LintelDepth7, D
(in.)
Number of barsand bar sizein top and
bottom of lintel
Steel yieldstrength8,
fy (psi)
Loading condition determined from Table 7.2
12 3 4 5
Maximum ground snow load (psf)
30 70 30 70 30 70 30 70
89
Span without stirrups11,12 2-7 2-9 2-0 2-1 2-0 2-0 2-0 2-0 2-0
1 – #440,000 5-2 5-5 4-0 4-3 3-7 3-3 2-11 2-4 2-3
60,000 5-9 6-3 4-0 4-3 3-7 3-3 2-11 2-4 2-3
1 – #540,000 5-9 6-3 4-0 4-3 3-7 3-3 2-11 2-4 2-3
60,000 5-9 6-3 4-0 4-3 3-7 3-3 2-11 2-4 2-3
2 – #41 – #6
40,000 5-9 6-3 4-0 4-3 3-7 3-3 2-11 2-4 2-3
60,000 DR DR DR DR DR DR DR DR DR
Center distance A13,14 0-9 0-10 0-6 0-6 0-5 0-5 0-4 STL STL
129
Span without stirrups11,12 2-11 3-1 2-6 2-7 2-5 2-4 2-3 2-1 2-0
1 – #440,000 5-9 6-2 4-8 4-10 4-4 4-1 3-9 3-2 3-1
60,000 8-0 8-7 6-6 6-9 6-0 5-5 4-11 3-11 3-10
1 – #540,000 8-1 8-9 6-8 6-11 6-0 5-5 4-11 3-11 3-10
60,000 9-1 10-3 6-8 7-0 6-0 5-5 4-11 3-11 3-102 – #41 – #6 40,000 9-1 9-9 6-8 7-0 6-0 5-5 4-11 3-11 3-10
Center distance A13,14 1-3 1-5 0-10 0-11 0-9 0-8 0-6 STL STL
169
Span without stirrups11,12 4-0 4-4 3-6 3-7 3-4 3-3 3-1 2-10 2-10
1 – #440,000 6-7 7-3 5-6 5-9 5-2 4-10 4-6 3-9 3-8
60,000 8-0 8-10 6-9 7-0 6-3 5-11 5-5 4-7 4-5
1 – #540,000 8-2 9-0 6-11 7-2 6-5 6-0 5-7 4-8 4-6
60,000 11-5 12-6 9-3 9-9 8-4 7-7 6-10 5-6 5-4
2 – #41 – #6
40,000 10-7 11-7 8-11 9-3 8-3 7-7 6-10 5-6 5-4
60,000 12-2 14-0 9-3 9-9 8-4 7-7 6-10 5-6 5-4
2 – #540,000 12-2 14-2 9-3 9-9 8-4 7-7 6-10 5-6 5-4
60,000 DR DR DR DR DR DR DR DR DR
Center distance A13,14 1-8 2-0 1-2 1-3 1-0 0-11 0-9 STL STL
209
Span without stirrups11,12 5-0 5-6 4-6 4-7 4-3 4-1 4-0 3-8 3-8
1 – #440,000 7-2 8-2 6-3 6-6 5-10 5-6 5-1 4-3 4-2
60,000 8-11 9-11 7-8 7-11 7-1 6-8 6-2 5-2 5-0
1 – #540,000 9-1 10-2 7-9 8-1 7-3 6-10 6-4 5-4 5-2
60,000 12-8 14-2 10-11 11-3 10-2 9-6 8-9 7-1 6-10
2 – #41 – #6
40,000 10-3 11-5 8-9 9-1 8-2 7-8 7-1 6-0 5-10
60,000 14-3 15-11 11-9 12-5 10-8 9-9 8-9 7-1 6-10
2 – #540,000 14-6 16-3 11-6 12-1 10-4 9-6 8-6 6-11 6-8
60,000 DR DR DR DR DR DR DR DR DR
Center distance A13,14 2-0 2-6 1-6 1-7 1-3 1-1 1-0 STL STL
2410
Span without stirrups11,12 6-0 6-8 5-5 5-7 5-3 5-0 4-10 4-6 4-5
1 – #440,000 7-11 9-0 6-11 7-2 6-5 6-0 5-7 4-8 4-7
60,000 9-8 10-11 8-5 8-9 7-10 7-4 6-10 5-9 5-7
1 – #540,000 9-10 11-2 8-7 8-11 8-0 7-6 7-0 5-10 5-8
60,000 12-0 13-7 10-6 10-10 9-9 9-2 8-6 7-2 6-11
2 – #41 – #6
40,000 11-1 12-7 9-8 10-1 9-1 8-6 7-10 6-7 6-5
60,000 15-6 17-7 13-6 14-0 12-8 11-10 10-8 8-7 8-4
2 – #540,000 15-6 17-11 12-8 13-4 11-6 10-7 9-7 7-10 7-7
60,000 DR DR DR DR DR DR DR DR DR
Center distance A13,14 2-4 3-0 1-9 1-11 1-6 1-4 1-2 STL STL
Maximum clear span of lintel (ft–inches)
For SI: 1 inch = 25.4 mm; 1 psf = 0.0479 kN/m2; 1 ft = 0.3048 m; Grade 40 = 280 MPa; Grade 60 = 420 MPa
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Chapter 7 – Requirements for Lintels and Reinforcement Around Openings
Notes for Tables 7.11 through 7.141 Where lintels are formed with waffle-grid forms, form material shall be removed, if necessary, to create top and bottom flanges of the lintel that
are not less than 3 inches (76 mm) in depth (in the vertical direction), are not less than 5 inches (127 mm) in width for 6-inch (156 mm) nominalwaffle-grid forms and not less than 7 inches (178 mm) in width for 8-inch (203 mm) nominal waffle-grid forms. See Figure 7.4. Flat stay-in-placeform lintels shall be permitted to be used in lieu of waffle-grid lintels. See Tables 7.3 through 7.10.
2 See Table 2.1 for tolerances permitted from nominal thicknesses and minimum dimensions and spacing of cores.3 Table values are based on concrete with a minimum specified compressive strength of 2,500 psi (17.2 MPa). See notes 12 and 14. Table values
are based on uniform loading. See Section 7.2 for lintels supporting concentrated loads. 4 Deflection criterion is L/240, where L is the clear span of the lintel in inches, or 1⁄2-inch (13 mm), whichever is less.5 Linear interpolation is permitted between ground snow loads.6 DR indicates design required STL – stirrups required throughout lintel7 Lintel depth, D, is permitted to include the available height of wall located directly above the lintel, provided that the increased lintel depth
spans the entire length of the lintel.8 Stirrups shall be fabricated from reinforcing bars with the same yield strength as that used for the main longitudinal reinforcement.9 Lintels less than 24 inches (610 mm) in depth with stirrups shall be formed from flat-walls forms (see Tables 7.3 through 7.10), or, if necessary,
form material shall be removed from waffle-grid forms so as to provide the required cover for stirrups. Allowable spans for lintels formed withflat-wall forms shall be determined from Tables 7.3 through 7.10.
10 Where stirrups are required for 24-inch (610 mm) deep lintels, the spacing shall not exceed 12 inches (305 mm) on center.11 Allowable clear span without stirrups applicable to all lintels of the same depth, D. Top and bottom reinforcement for lintels without stirrups
shall not be less than the least amount of reinforcement required for a lintel of the same depth and loading condition with stirrups. All otherspans require stirrups spaced at not more than d/2.
12 Where concrete with a minimum specified compressive strength of 3,000 psi (20.7 MPa) is used, clear spans for lintels without stirrups shall bepermitted to be multiplied by 1.05. If the increased span exceeds the allowable clear span for a lintel of the same depth and loading conditionwith stirrups, the top and bottom reinforcement shall be equal to or greater than that required for a lintel of the same depth and loading condi-tion that has an allowable clear span that is equal to or greater than that of the lintel without stirrups that has been increased.
13 Center distance, A, is the center portion of the span where stirrups are not required. This is applicable to all longitudinal bar sizes and steel yieldstrengths.
14 Where concrete with a minimum specified compressive strength of 3,000 psi (20.7 MPa) is used, center distance, A, shall be permitted to be multi-plied by 1.10.
15 The maximum clear opening width between two solid wall segments shall be 18 feet (5.5 m). See Section 5.2.1. Lintel spans in table greater than18 feet are shown for interpolation and information purposes only.
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Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
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Table 7.12. Maximum Allowable Clear Spans for 6-inch Thick Waffle-Grid Lintels in Load-Bearing Walls1,2,3,4,5,6,15
Maximum Roof Clear Span of 32 feet and Maximum Floor Clear Span of 24 feet
LintelDepth7, D
(in.)
Number of barsand bar sizein top and
bottom of lintel
Steel yieldstrength8,
fy (psi)
Loading condition determined from Table 7.2
1
2 3 4 5
Maximum ground snow load (psf)
30 70 30 70 30 70 30 70
89
Span without stirrups11,12 3-0 3-2 2-3 2-4 2-1 2-0 2-0 2-0 2-0
1 – #440,000 5-10 6-1 4-7 4-10 4-3 3-9 3-4 2-8 2-7
60,000 7-0 7-4 4-9 5-1 4-3 3-9 3-4 2-8 2-7
1 – #540,000 7-0 7-5 4-9 5-1 4-3 3-9 3-4 2-8 2-7
60,000 7-0 7-6 4-9 5-1 4-3 3-9 3-4 2-8 2-7
Center distance A13,14 1-0 1-1 0-7 0-8 0-6 0-6 0-5 0-3 0-3
129
Span without stirrups11,12 3-3 3-5 2-8 2-9 2-7 2-5 2-4 2-1 2-1
1 – #440,000 6-5 6-10 5-3 5-5 4-10 4-6 4-1 3-6 3-4
60,000 8-11 9-6 7-3 7-7 6-9 6-2 5-6 4-5 4-3
1 – #540,000 9-1 9-8 7-5 7-9 6-11 6-2 5-6 4-5 4-3
60,000 11-0 11-8 7-10 8-4 7-0 6-2 5-6 4-5 4-3
2 – #41 – #6
40,000 10-3 10-11 7-10 8-4 7-0 6-2 5-6 4-5 4-3
60,000 11-0 12-3 7-10 8-4 7-0 6-2 5-6 4-5 4-3
Center distance A13,14 1-7 1-9 1-0 1-1 0-11 0-9 0-8 0-5 0-5
169
Span without stirrups11,12 4-4 4-9 3-9 3-11 3-7 3-5 3-3 3-0 2-11
1 – #440,000 7-4 8-0 6-2 6-5 5-9 5-3 4-11 4-1 4-0
60,000 9-0 9-9 7-6 7-10 7-0 6-5 5-11 5-0 4-10
1 – #540,000 9-2 10-0 7-8 8-0 7-1 6-7 6-1 5-1 5-0
60,000 12-9 13-11 10-8 11-1 9-9 8-7 7-8 6-1 5-11
2 – #41 – #6
40,000 11-10 12-11 9-11 10-3 9-2 8-6 7-8 6-1 5-11
60,000 14-3 15-7 10-11 11-7 9-9 8-7 7-8 6-1 5-11
2 – #540,000 14-6 15-10 10-11 11-7 9-9 8-7 7-8 6-1 5-11
60,000 DR DR DR DR DR DR DR DR DR
Center distance A13,14 2-0 2-5 1-5 1-6 1-3 1-1 0-11 0-8 0-7
209
Span without stirrups11,12 5-5 6-1 4-10 5-0 4-7 4-4 4-2 3-10 3-9
1 – #440,000 8-1 9-0 7-0 7-3 6-6 6-0 5-6 4-8 4-6
60,000 9-11 11-0 8-6 8-10 7-11 7-3 6-9 5-8 5-6
1 – #540,000 10-1 11-3 8-8 9-0 8-1 7-5 6-11 5-9 5-8
60,000 14-1 15-8 12-1 12-7 11-3 10-5 9-7 7-10 7-7
2 – #41 – #6
40,000 11-4 12-8 9-9 10-2 9-1 8-5 7-9 6-6 6-4
60,000 15-10 17-8 13-7 14-2 12-5 11-0 9-10 7-10 7-7
2 – #540,000 16-1 18-0 13-5 14-4 12-1 10-9 9-7 7-8 7-5
60,000 DR DR DR DR DR DR DR DR DR
Center distance A13,14 2-5 3-1 1-10 2-0 1-7 1-4 1-2 0-10 0-9
2410
Span without stirrups11,12 6-6 7-4 5-10 6-0 5-7 5-3 5-1 4-8 4-7
1 – #440,000 8-8 9-11 7-8 8-0 7-2 6-7 6-1 5-2 5-0
60,000 10-7 12-1 9-4 9-9 8-9 8-1 7-5 6-3 6-1
1 – #540,000 10-10 12-4 9-6 9-11 8-11 8-3 7-7 6-5 6-3
60,000 13-2 15-0 11-8 12-1 10-10 10-0 9-3 7-9 7-7
2 – #41 – #6
40,000 12-3 13-11 10-9 11-2 10-0 9-3 8-7 7-3 7-0
60,000 17-1 19-5 15-0 15-7 14-0 12-11 12-0 9-7 9-3
2 – #540,000 17-5 19-10 14-9 15-8 13-4 11-11 10-9 8-8 8-5
60,000 DR DR DR DR DR DR DR DR DR
Center distance A13,14 2-10 3-8 2-2 2-4 1-11 1-7 1-5 1-0 0-11
For SI: 1 inch = 25.4 mm; 1 psf = 0.0479 kN/m2; 1 ft = 0.3048 m; Grade 40 = 280 MPa; Grade 60 = 420 MPaSee Page 7-17 for notes.
Maximum clear span of lintel (ft–inches)
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Chapter 7 – Requirements for Lintels and Reinforcement Around Openings
Table 7.13. Maximum Allowable Clear Spans for 8-inch Thick Waffle-Grid Lintels in Load-Bearing Walls1,2,3,4,5,6,15
Maximum Roof Clear Span of 40 feet and Maximum Floor Clear Span of 32 feet
LintelDepth7, D
(in.)
Number of barsand bar sizein top and
bottom of lintel
Steel yield strength8,
fy (psi)
Loading condition determined from Table 7.2
1
2 3 4 5
Maximum ground snow load (psf)
30 70 30 70 30 70 30 70
89
Span without stirrups11,12 2-6 2-9 2-0 2-1 2-0 2-0 2-0 2-0 2-0
1 – #440,000 4-5 4-9 3-7 3-9 3-4 3-0 2-10 2-3 2-2
60,000 5-6 6-2 4-0 4-3 3-7 3-1 2-10 2-3 2-2
1 – #5 40,000 5-6 6-2 4-0 4-3 3-7 3-1 2-10 2-3 2-2
Center distance A13,14 0-9 0-10 0-6 0-6 0-5 0-4 0-4 STL STL
129
Span without stirrups11,12 2-10 3-1 2-6 2-7 2-5 2-3 2-2 2-0 2-0
1 – #440,000 5-7 6-1 4-8 4-10 4-4 3-11 3-8 3-0 2-11
60,000 6-9 7-5 5-8 5-11 5-4 4-9 4-5 3-8 3-7
1 – #540,000 6-11 7-7 5-10 6-0 5-5 4-10 4-6 3-9 3-7
60,000 8-8 10-1 6-7 7-0 5-11 5-2 4-8 3-9 3-7
2 – #41 – #6
40,000 8-8 9-10 6-7 7-0 5-11 5-2 4-8 3-9 3-7
60,000 8-8 10-1 6-7 7-0 5-11 5-2 4-8 3-9 3-7
Center distance A13,14 1-2 1-5 0-10 0-11 0-9 0-7 0-6 STL STL
169
Span without stirrups11,12 3-10 4-3 3-6 3-7 3-4 3-2 3-0 2-10 2-9
1 – #440,000 6-5 7-2 5-6 5-9 5-2 4-8 4-4 3-7 3-6
60,000 7-9 8-9 6--9 7-0 6-3 5-8 5-3 4-4 4-3
1 – #540,000 7-11 8-11 6-10 7-1 6-5 5-9 5-4 4-5 4-4
60,000 9-8 10-11 8-4 8-8 7-10 7-0 6-6 5-2 5-1
2 – #41 – #6
40,000 9-0 10-1 7-9 8-0 7-3 6-6 6-1 5-0 4-11
60,000 11-5 13-10 9-2 9-8 8-3 7-2 6-6 5-2 5-1
Center distance A13,14 1-6 1-11 1-2 1-3 1-0 0-10 0-8 STL STL
209
Span without stirrups11,12 4-10 5-5 4-5 4-7 4-3 4-0 3-11 3-7 3-7
1 – #440,000 7-0 8-1 6-3 6-5 5-10 5-3 4-11 4-1 3-11
60,000 8-7 9-10 7-7 7-10 7-1 6-5 6-0 4-11 4-10
1 – #540,000 8-9 10-1 7-9 8-0 7-3 6-6 6-1 5-1 4-11
60,000 10-8 12-3 9-6 9-10 8-10 8-0 7-5 6-2 6-0
2 – #41 – #6
40,000 9-10 11-4 8-9 9-1 8-2 7-4 6-10 5-8 5-7
60,000 12-0 13-10 10-8 11-0 9-11 9-0 8-4 6-8 6-6
2 – #540,000 12-3 14-1 10-10 11-3 10-2 8-11 8-1 6-6 6-4
60,000 14-0 17-6 11-8 12-3 10-6 9-1 8-4 6-8 6-6
Center distance A13,14 1-10 2-5 1-5 1-7 1-3 1-0 0-11 STL STL
2410
Span without stirrups11,12 5-9 6-7 5-5 5-6 5-2 4-11 4-9 4-5 4-4
1 – #440,000 7-6 8-10 6-10 7-1 6-5 5-9 5-5 4-6 4-4
60,000 9-2 10-9 8-4 8-8 7-10 7-1 6-7 5-6 5-4
1 – #540,000 9-5 11-0 8-6 8-10 8-0 7-2 6-8 5-7 5-5
60,000 11-5 13-5 10-5 10-9 9-9 8-9 8-2 6-10 6-8
2 – #41 – #6
40,000 10-7 12-5 9-8 10-0 9-0 8-1 7-7 6-3 6-2
60,000 12-11 15-2 11-9 12-2 11-0 9-11 9-3 7-8 7-6
2 – #540,000 13-2 15-6 12-0 12-5 11-2 9-11 9-2 7-5 7-3
60,000 16-3 21-0 14-1 14-10 12-9 11-1 10-1 8-1 7-11
2 – #6 40,000 14-4 18-5 12-6 13-2 11-5 9-11 9-2 7-5 7-3
Center distance A13,14 2-1 2-11 1-9 1-10 1-6 1-3 1-1 STL STL
For SI: 1 inch = 25.4 mm; 1 psf = 0.0479 kN/m2; 1 ft = 0.3048 m; Grade 40 = 280 MPa; Grade 60 = 420 MPaSee Page 7-17 for notes.
Maximum clear span of lintel (ft–inches)
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Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
7-20
Table 7.14. Maximum Allowable Clear Spans for 8-inch Thick Waffle-Grid Lintels in Load-Bearing Walls1,2,3,4,5,6,15
Maximum Roof Clear Span of 32 feet and Maximum Floor Clear Span of 24 feet
LintelDepth7, D
(in.)
Number of barsand bar sizein top and
bottom of lintel
Steel yield strength8,
fy (psi)
Loading condition determined from Table 7.2
12 3 4 5
Maximum ground snow load (psf)
30 70 30 70 30 70 30 70
89
Span without stirrups11,12 2-11 3-2 2-3 2-4 2-1 2-0 2-0 2-0 2-0
1 – #440,000 5-0 5-3 4-0 4-2 3-9 3-3 3-1 2-5 2-5
60,000 6-9 7-4 4-9 5-0 4-3 3-6 3-2 2-5 2-5
1 – #540,000 6-9 7-5 4-9 5-0 4-3 3-6 3-2 2-5 2-5
60,000 6-9 7-5 4--9 5-0 4-3 3-6 3-2 2-5 2-5
Center distance A13,14 0-11 1-1 0-7 0-8 0-6 0-5 0-4 STL STL
129
Span without stirrups11,12 3-1 3-5 2-8 2-9 2-7 2-4 2-3 2-1 2-1
1 – #440,000 6-3 6-9 5-2 5-5 4-10 4-3 4-0 3-3 3-2
60,000 7-7 8-3 6-4 6-7 5-11 5-2 4-10 4-0 3-11
1 – #540,000 7-9 8-5 6-6 6-9 6-0 5-3 4-11 4-1 4-0
60,000 10-4 11-9 7-9 8-3 6-11 5-9 5-2 4-1 4-0
2 – #41 – #6
40,000 10-0 10--11 7--9 8-3 6-11 5-9 5-2 4-1 4-0
60,000 10-4 12-0 7-9 8-3 6-11 5-9 5-2 4-1 4-0
Center distance A13,14 1-5 1-9 1-0 1-1 0-11 0-8 0-7 STL STL
169
Span without stirrups11,12 4-2 4-8 3-9 3-10 3-7 3-3 3-2 2-11 2-10
1 – #440,000 7-1 7-11 6-2 6-4 5-8 5-0 4-8 3-10 3-9
60,000 8-7 9-8 7-6 7-9 7-0 6--2 5-8 4-9 4-7
1 – #540,000 8-9 9-11 7-8 7-11 7-1 6-3 5-10 4-10 4-8
60,000 10-8 12-0 9-3 9-8 8-8 7-7 7-1 5-8 5-6
2 – #41 – #6
40,000 9-11 11-2 8-7 8-11 8-0 7-1 6-7 5-5 5-4
60,000 13-6 15-6 10-9 11-5 9-7 8-0 7-3 5-8 5-6
2 – #5 40,000 13-6 15-10 10-9 11-5 9-7 8-0 7-3 5-8 5-6
Center distance A13,14 1-10 2-4 1-5 1-6 1-3 0-11 0-10 STL STL
209
Span without stirrups11,12 5-2 5-11 4-9 4-11 4-6 4-2 4-0 3-9 3-8
1 – #440,000 7-8 8-11 6-11 7-2 6-5 5-8 5-3 4-5 4-3
60,000 9-5 10-10 8-5 8-9 7-10 6-11 6-5 5-4 5-3
1 – #540,000 9-7 11-1 8-7 8-11 8-0 7-1 6-7 5-6 5-4
60,000 11-8 13-6 10-6 10-11 9-9 8-7 8-0 6-8 6-6
2 – #41 – #6
40,000 10-10 12-6 9-9 10-1 9-1 8-0 7-5 6-2 6-0
60,000 13-2 15-3 11-10 12-3 11-0 9-9 9-1 7-3 7-1
2 – #540,000 13-5 15-7 12-1 12-6 11-3 9-11 9-0 7-1 6-11
60,000 16-3 20-8 13-8 14-6 12-3 10-2 9-3 7-3 7-1
2 – #6 40,000 15-9 20-0 13-3 14-1 11-11 9-11 9-0 7-1 6-11
Center distance A13,15 2-2 2-11 1-9 1-11 1-6 1-2 1-0 STL STL
2410
Span without stirrups11,12 6-2 7-2 5-10 6-0 5-6 5-1 4-11 4-6 4-6
1 – #440,000 8-3 9-9 7-7 7-11 7-1 6-3 5-10 4-10 4-9
60,000 10-0 11-11 9-3 9-7 8-8 7-8 7-1 5-11 5-9
1 – #540,000 10-3 12-2 9-5 9-10 8-10 7-9 7-3 6-0 5-11
60,000 12-6 14-10 11-6 12-0 10-9 9-6 8-10 7-4 7-2
2 – #41 – #6
40,000 11-7 13-8 10-8 11-1 10-0 8-9 8-2 6-10 6-8
60,000 14-1 16-8 13-0 13-6 12-2 10-9 10-0 8-3 8-1
2 – #540,000 14-5 17-0 13-3 13-9 12-5 10-11 10-1 8-1 7-10
60,000 18-8 23-9 16-6 17-6 14-10 12-4 11-3 8-10 8-7
2 – #6 40,000 16-5 21-6 14-6 15-5 13-1 11-0 10-1 8-1 7-10
Center distance A13,15 2-6 3-6 2-2 2-4 1-10 1-5 1-3 STL STL
For SI: 1 inch = 25.4 mm; 1 psf = 0.0479 kN/m2; 1 ft = 0.3048 m; Grade 40 = 280 MPa; Grade 60 = 420 MPaSee Page 7-17 for notes.
Maximum clear span of lintel (ft–inches)
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Chapter 7 – Requirements for Lintels and Reinforcement Around Openings
Table 7.15. Maximum Allowable Clear Spans for 6-inch Thick Screen-Grid Lintels in Load-Bearing Walls1,2,3,4,5,6,16
Roof Clear Span 40 feet and Floor Clear Span 32 feet
LintelDepth7, D
(in.)
Number of barsand bar sizein top and
bottom of lintel
Steel yieldstrength8,
fy (psi)
Loading condition determined from Table 7.2
1
2 3 4 5
Maximum ground snow load (psf)
30 70 30 70 30 70 30 70
129,10 Span without stirrups13 2-9 2-11 2-4 2-5 2-3 2-3 2-2 2-0 2-0
169,10 Span without stirrups13 3-9 4-0 3-4 3-5 3-2 3-1 3-0 2-9 2-9
209,10 Span without stirrups13 4-9 5-1 4-3 4-4 4-1 4-0 3-10 3-7 3-7
2411
Span without stirrups12,13 5-8 6-3 5-2 5-3 5-0 4-10 4-8 4-4 4-4
1 – #440,000 7-11 9-0 6-11 7-2 6-5 6-1 5-8 4-9 4-7
60,000 9-9 11-0 8-5 8-9 7-10 7-5 6-10 5-9 5-7
1 – #540,000 9-11 11-2 8-7 8-1 8-0 7-7 7-0 5--11 5-9
60,000 12-1 13-8 10-6 10-10 9-9 9-3 8-6 7-2 7-0
2 – #41 – #6
40,000 11-2 12-8 9-9 10-1 9-1 8-7 7-11 6-8 6-6
60,000 15-7 17-7 12-8 13-4 11-6 10-8 9-8 7-11 7-8
2 – #540,000 14-11 18-0 12-2 12-10 11-1 10-3 9-4 7-8 7-5
60,000 DR DR DR DR DR DR DR DR DR
Center distance A14,15 2-0 2-6 1-6 1-7 1-4 1-2 1-0 STL STL
For SI: 1 inch = 25.4 mm; 1 psf = 0.0479 kN/m2; 1 ft = 0.3048 m; Grade 40 = 280 MPa; Grade 60 = 420 MPa1 Where lintels are formed with screen-grid forms, form material shall be removed if necessary to create top and bottom flanges of the lintel that
are not less than 5 inches (127 mm) in width and not less than 2.5 inches (64 mm) in depth (in the vertical direction). See Figure 7.5. Flat stay-in-place form lintels shall be permitted to be used in lieu of screen-grid lintels. See Tables 7.3 through 7.10.
2 See Table 2.1 for tolerances permitted from nominal thickness and minimum dimensions and spacings of cores.3 Table values are based on concrete with a minimum specified compressive strength of 2,500 psi (17.2 MPa). See notes 13 and 15. Table values
are based on uniform loading. See Section 7.2 for lintels supporting concentrated loads. 4 Deflection criterion is L/240, where L is the clear span of the lintel in inches, or 1⁄2-inch (13 mm), whichever is less.5 Linear interpolation is permitted between ground snow loads.6 DR indicates design required STL indicates stirrups required throughout lintel7 Lintel depth, D, is permitted to include the available height of wall located directly above the lintel, provided that the increased lintel depth
spans the entire length of the lintel.8 Stirrups shall be fabricated from reinforcing bars with the same yield strength as that used for the main longitudinal reinforcement.9 Stirups are not required for lintels less than 24 inches (610 mm) in depth fabricated from screen-grid forms. Top and bottom reinforcement shall
consist of a No. 4 bar having a yield strength of 40,000 psi (280 MPa) or 60,000 psi (420 MPa). 10 Lintels between 12 (305) and 24 inches (610 mm) in depth with stirrups shall be formed from flat-walls forms (see Tables 7.3 through 7.10), or
form material shall be removed from screen-grid forms so as to provide a concrete section comparable to that required for a flat wall. Allowablespans for flat lintels with stirrups shall be determined from Tables 7.3 through 7.10.
11 Where stirrups are required for 24-inch (610 mm) deep lintels, the spacing shall not exceed 12 inches (305 mm) on center. 12 Allowable clear span without stirrups applicable to all lintels of the same depth, D. Top and bottom reinforcement for lintels without stirrups
shall not be less than the least amount of reinforcement required for a lintel of the same depth and loading condition with stirrups. All otherspans require stirrups spaced at not more than 12 inchs (305 mm).
13 Where concrete with a minimum specified compressive strength of 3,000 psi (20.7 MPa) is used, clear spans for lintels without stirrups shall bepermitted to be multiplied by 1.05. If the increased span exceeds the allowable clear span for a lintel of the same depth and loading conditionwith stirrups, the top and bottom reinforcement shall be equal to or greater than that required for a lintel of the same depth and loading condi-tion that has an allowable clear span that is equal to or greater than that of the lintel without stirrups that has been increased.
14 Center distance, A, is the center portion of the span where stirrups are not required. This is applicable to all longitudinal bar sizes and steel yieldstrengths.
15 Where concrete with a minimum specified compressive strength of 3,000 psi (20.7 MPa) is used, center distance, A, shall be permitted to be multi-plied by 1.10.
16 The maximum clear opening width between two solid wall segments shall be 18 feet (5.5 m). See Section 5.2.1. Lintel spans in table greater than18 feet (5.5 m) are shown for interpolation and information purposes only.
Maximum clear span of lintel (ft–inches)
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Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
7-22
Table 7.16. Maximum Allowable Clear Spans for 6-inch Thick Screen-Grid Lintels in Load-Bearing Walls1,2,3,4,5,6,16
Roof Clear Span 32 feet and Floor Clear Span 24 feet
LintelDepth7, D
(in.)
Number of barsand bar sizein top and
bottom of lintel
Steel yieldstrength8,
fy (psi)
Loading condition determined from Table 7.2
1
2 3 4 5
Maximum ground snow load (psf)
30 70 30 70 30 70 30 70
129,10 Span without stirrups13 3-0 3-2 2-6 2-7 2-5 2-4 2-3 2-1 2-0
169,10 Span without stirrups13 4-1 4-5 3-6 3-8 3-5 3-3 3-1 2-11 2-10
209,10 Span without stirrups13 5-1 5-7 4-6 4-8 4-4 4-2 4-0 3-8 3-8
2411
Span without stirrups12,13 6-1 6-9 5-6 5-8 5-3 5-1 4-10 4-6 4-6
1 – #440,000 8-9 9-11 7-8 8-0 7-2 6-8 6-2 5-2 5-0
60,000 10-9 12-2 9-4 9-9 8-9 8-1 7-6 6-4 6-2
1 – #540,000 10-11 12-5 9-7 9-11 8-11 8-3 7-8 6-6 6-3
60,000 13-4 15-1 11-8 12-1 10-10 10-1 9-4 7-10 7-8
2 – #41 – #6
40,000 12-4 14-0 10-9 11-3 10-0 9-4 8-8 7-3 7-1
60,000 16-7 18-0 14-10 15-8 13-4 12-0 10-10 8-9 8-6
2 – #540,000 16-7 18-0 14-2 15-0 12-9 11-7 10-5 8-5 8-2
60,000 DR DR DR DR DR DR DR DR DR
Center distance A14,15 2-5 3-1 1-10 2-0 1-7 1-5 1-2 STL STL
For SI: 1 inch = 25.4 mm; 1 psf = 0.0479 kN/m2; 1 ft = 0.3048 m; Grade 40 = 280 MPa; Grade 60 = 420 MPa1 Where lintels are formed with screen-grid forms, form material shall be removed if necessary to create top and bottom flanges of the lintel that
are not less than 5 inches (127 mm) in width and not less than 2.5 inches (64 mm) in depth (in the vertical direction). See Figure 7.5. Flat stay-in-place form lintels shall be permitted to be used in lieu of screen-grid lintels. See Tables 7.3 through 7.10.
2 See Table 2.1 for tolerances permitted from nominal thickness and minimum dimensions and spacings of cores.3 Table values are based on concrete with a minimum specified compressive strength of 2,500 psi (17.2 MPa). See notes 13 and 15. Table values
are based on uniform loading. See Section 7.2 for lintels supporting concentrated loads. 4 Deflection criterion is L/240, where L is the clear span of the lintel in inches, or 1⁄2-inch (13 mm), whichever is less.5 Linear interpolation is permitted between ground snow loads.6 DR indicates design required STL indicates stirrups required throughout lintel7 Lintel depth, D, is permitted to include the available height of wall located directly above the lintel, provided that the increased lintel depth
spans the entire length of the lintel.8 Stirrups shall be fabricated from reinforcing bars with the same yield strength as that used for the main longitudinal reinforcement.9 Stirups are not required for lintels less than 24 inches (610 mm) in depth fabricated from screen-grid forms. Top and bottom reinforcement shall
consist of a No. 4 bar having a yield strength of 40,000 psi (280 MPa) or 60,000 psi (420 MPa). 10 Lintels between 12 (305) and 24 inches (610 mm) in depth with stirrups shall be formed from flat-walls forms (see Tables 7.3 through 7.10), or
form material shall be removed from screen-grid forms so as to provide a concrete section comparable to that required for a flat wall. Allowablespans for flat lintels with stirrups shall be determined from Tables 7.3 through 7.10.
11 Where stirrups are required for 24-inch (610 mm) deep lintels, the spacing shall not exceed 12 inches (305 mm) on center. 12 Allowable clear span without stirrups applicable to all lintels of the same depth, D. Top and bottom reinforcement for lintels without stirrups
shall not be less than the least amount of reinforcement required for a lintel of the same depth and loading condition with stirrups. All otherspans require stirrups spaced at not more than 12 inchs (305 mm).
13 Where concrete with a minimum specified compressive strength of 3,000 psi (20.7 MPa) is used, clear spans for lintels without stirrups shall bepermitted to be multiplied by 1.05. If the increased span exceeds the allowable clear span for a lintel of the same depth and loading conditionwith stirrups, the top and bottom reinforcement shall be equal to or greater than that required for a lintel of the same depth and loading condi-tion that has an allowable clear span that is equal to or greater than that of the lintel without stirrups that has been increased.
14 Center distance, A, is the center portion of the span where stirrups are not required. This is applicable to all longitudinal bar sizes and steel yieldstrengths.
15 Where concrete with a minimum specified compressive strength of 3,000 psi (20.7 MPa) is used, center distance, A, shall be permitted to be multi-plied by 1.10.
16 The maximum clear opening width between two solid wall segments shall be 18 feet (5.5 m). See Section 5.2.1. Lintel spans in table greater than18 feet (5.5 m) are shown for interpolation and information purposes only.
Maximum clear span of lintel (ft–inches)
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Chapter 7 – Requirements for Lintels and Reinforcement Around Openings
Table 7.17. Maximum Allowable Clear Spans for Flat Lintels Without Stirrups in Non-Load-Bearing Walls 1,2,3,4,5,7,8
For SI: 1 inch = 25.4 mm; 1 psf = 0.0479 kN/m2; 1 ft = 0.3048 m; Grade 40 = 280 MPa; Grade 60 = 420 MPa1 See Table 2.1 for tolerances permitted from nominal thickness.2 Table values are based on concrete with a minimum specified compressive strength of 2,500 psi (17.2 MPa). See note 5.3 Deflection criterion is L/240, where L is the clear span of the lintel in inches, or 1⁄2-inch (13 mm), whichever is less.4 Linear interpolation between lintels depths, D, is permitted provided the two cells being used to interpolate are shaded .5 Where concrete with a minimum specified compressive strength of 3,000 psi (20.7 MPa) is used, spans in cells that are shaded shall be permitted
to be multiplied by 1.05.6 Lintel depth, D, is permitted to include the available height of wall located directly above the lintel, provided that the increased lintel depth
spans the entire length of the lintel.7 DR indicates design required8 The maximum clear opening width between two solid wall segments shall be 18 feet (5.5 m). See Section 5.2.1. Lintel spans in table greater than
18 feet are shown for interpolation and information purposes only.
LintelDepth6, D
(in.)
Number of barsand bar size
Steel yieldstrength,fy (psi)
Nominal Wall Thickness (inches)
4 6 8 10
Construction of wall above lintel
Concretewall
Lightframedgable
Concretewall
Lightframedgable
Concretewall
Lightframedgable
Concretewall
Lightframedgable
8
1 – #440,000 10-11 11-5 9-7 11-2 7-10 9-5 7-3 9-260,000 12-5 11-7 10-11 13-5 9-11 13-2 9-3 12-10
1 – #540,000 12-7 11-7 11-1 13-8 10-1 13-5 9-4 13-160,000 DR DR 12-7 16-4 11-6 14-7 10-9 14-6
2 – #41 – #6
40,000 DR DR 12-0 15-3 10-11 15-0 10-2 14-860,000 DR DR DR DR 12-2 15-3 11-7 15-3
2 – #540,000 DR DR DR DR 12-7 16-7 11-9 16-760,000 DR DR DR DR DR DR 13-3 16-7
2 – #640,000 DR DR DR DR DR DR 13-2 17-860,000 DR DR DR DR DR DR DR DR
12
1 – #440,000 11-5 9-10 10-6 12-0 9-6 11-6 8-9 11-160,000 11-5 9-10 11-8 13-3 10-11 14-0 10-1 13-6
1 – #540,000 11-5 9-10 11-8 13-3 11-1 14-4 10-3 13-960,000 11-5 9-10 11-8 13-3 11-10 16-0 11-9 16-9
2 – #41 – #6
40,000 DR DR 11-8 13-3 11-10 16-0 11-2 15-660,000 DR DR 11-8 13-3 11-10 16-0 11-11 18-4
2 – #540,000 DR DR 11-8 13-3 11-10 16-0 11-11 18-460,000 DR DR 11-8 13-3 11-10 16-0 11-11 18-4
16
1 – #440,000 13-6 13-0 11-10 13-8 10-7 12-11 9-11 12-460,000 13-6 13-0 13-8 16-7 12-4 15-9 11-5 15-0
1 – #540,000 13-6 13-0 13-10 17-0 12-6 16-1 11-7 15-460,000 13-6 13-0 13-10 17-1 14-0 19-7 13-4 18-8
2 – #41 – #6
40,000 13-6 13-0 13-10 17-1 13-8 18-2 12-8 17-460,000 13-6 13-0 13-10 17-1 14-0 20-3 14-1
2 – #540,000 13-6 13-0 13-10 17-1 14-0 20-3 14-160,000 DR DR 13-10 17-1 14-0 20-3 14-1
20
1 – #440,000 14-11 15-10 13-0 14-10 11-9 13-11 10-10 13-260,000 15-3 15-10 14-11 18-1 13-6 17-0 12-6 16-2
1 – #540,000 15-3 15-10 15-2 18-6 13-9 17-5 12-8 16-660,000 15-3 15-10 15-8 20-5 15-9 14-7 20-1
2 – #41 – #6
40,000 15-3 15-10 15-8 20-5 14-11 13-1060,000 15-3 15-10 15-8 20-5 15-10 15-11
2 – #540,000 15-3 15-10 15-8 20-5 15-10 15-1160,000 15-3 15-10 15-8 20-5 15-10 15-11
24
1 – #440,000 16-1 17-1 13-11 15-10 12-7 14-9 11-8 13-1060,000 16-11 18-5 16-1 19-3 14-6 18-0 13-5 17-0
1 – #540,000 16-11 18-5 16-3 19-8 14-9 18-5 13-8 17-460,000 16-11 18-5 17-4 17-0 15-8
2 – #41 – #6
40,000 16-11 18-5 17-4 16-1 14-1060,000 16-11 18-5 17-4 17-6 17-1
2 – #540,000 16-11 18-5 17-4 17-6 17-460,000 16-11 18-5 17-4 17-6 17-8
Maximum clear span of lintel (ft-inches)
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Table 7.18. Maximum Allowable Clear Spans for Waffle-Grid and Screen-Grid Lintels Without Stirrups in Non-Load-Bearing Walls 3,4,5,6,7
LintelDepth8, D
(in.)
Form type and nominal wall thickness (inches)
6-inch waffle-grid1 8-inch waffle-grid1 6-inch screen-grid2
Construction of wall above lintel
Concrete wall Light framed gable Concrete wall Light framed gable Concrete wall Light framed gable
8 10-3 8-8 8-8 8-3 — —
12 9-2 7-6 7-10 7-1 8-8 6-9
16 10-11 10-0 9-4 9-3 — —
20 12-5 12-2 10-7 11-2 — —
24 13-9 14-2 11-10 12-11 13-0 12-9
For SI: 1 inch = 25.4 mm; 1 psf = 0.0479 kN/m2; 1 ft = 0.3048 m1 Where lintels are formed with waffle-grid forms, form material shall be removed, if necessary, to create top and bottom flanges of the lintel that
are not less than 3 inches (76 mm) in depth (in the vertical direction), are not less than 5 inches (127 mm) in width for 6-inch (152 mm) waffle-grid forms and not less than 7 inches (178 mm) in width for 8-inch (203 mm) waffle-grid forms. See Figure 7.4. Flat stay-in-place form lintelsshall be permitted to be used in lieu of waffle-grid lintels. See Tables 7.3 through 7.10.
2 Where lintels are formed with screen-grid forms, form material shall be removed if necessary to create top and bottom flanges of the lintel thatare not less than 5 inches (127 mm) in width and not less than 2.5 inches (64 mm) in depth (in the vertical direction). See Figure 7.5. Flat stay-in-place form lintels shall be permitted to be used in lieu of screen-grid lintels. See Tables 7.3 through 7.10.
3 See Table 2.1 for tolerances permitted from nominal thickness and minimum dimensions and spacing of cores.4 Table values are based on concrete with a minimum specified compressive strength of 2,500 psi (17.2 MPa). See Note 7.5 Deflection criterion is L/240, where L is the clear span of the lintel in inches, or 1⁄2-inch (13 mm), whichever is less.6 Top and bottom reinforcement shall consist of a No. 4 bar having a minimum yield strength of 40,000 psi (280 MPa). 7 Where concrete with a minimum specified compressive strength of 3,000 psi (20.7 MPa) is used, spans in shaded cells shall be permitted to be
multiplied by 1.05.8 Lintel depth, D, is permitted to include the available height of wall located directly above the lintel, provided that the increased lintel depth
spans the entire length of the lintel.
Maximum clear span of lintel (ft–inches)
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Chapter 7 – Requirements for Lintels and Reinforcement Around Openings
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Table 7.19. Maximum Allowable Clear Spans for 4-inch Nominal Thick Flat Lintels in Top Story Walls Subject to Roof UpliftForces1,2,3,4,5,6,13
LintelDepth7, D
(in.)
Number of barsand bar sizein top and
bottom of lintel
Steel yieldstrength8,
fy (psi)
Factored roof uplift force from Table 7.1A (plf)
600 800 1000 1200 1400 1600 1800 2000 2200
Maximum clear span of lintel for uplift forces (ft-inches)
8
Span without stirrups9,10 5-6 4-1 3-3 2-8 2-3 2-0 2-0 2-0 2-0
1 – #440,000 8-3 7-1 6-4 5-9 5-4 5-0 4-8 4-5 4-360,000 9-10 8-5 7-6 6-10 6-4 5-11 5-4 4-9 4-4
1 – #5 40,000 10-0 8-7 7-8 7-0 6-5 6-0 5-4 4-9 4-4Center distance A11,12 5-6 4-1 3-3 2-8 2-3 2-0 2-0 2-0 2-0
12
Span without stirrups9,10 4-8 3-5 2-9 2-3 2-0 2-0 2-0 2-0 2-0
1 – #440,000 10-11 9-5 8-4 7-7 7-0 6-7 6-2 5-10 5-760,000 13-2 11-4 10-1 9-2 8-6 7-11 7-5 7-1 6-9
1 – #540,000 13-5 11-6 10-3 9-4 8-8 8-1 7-7 7-2 6-1060,000 16-1 13-10 12-3 11-2 10-4 9-8 8-11 8-0 7-3
2 – #41 – #6
40,000 15-0 12-11 11-6 10-5 9-8 9-0 8-6 8-0 7-360,000 17-10 15-4 13-8 12-5 11-5 10-1 8-11 8-0 7-3
Center distance A11,12 4-8 3-5 2-9 2-3 2-0 2-0 2-0 2-0 2-0
16
Span without stirrups9,10 6-9 4-11 3-11 3-2 2-9 2-4 2-1 2-0 2-0
1 – #440,000 13-2 11-3 10-0 9-1 8-5 7-10 7-5 7-0 6-860,000 16-0 13-8 12-2 11-1 10-2 9-6 8-11 8-6 8-1
1 – #540,000 16-4 13-11 12-5 11-3 10-5 9-8 9-2 8-8 8-360,000 16-10 14-11 13-7 12-6 11-8 11-0 10-5 9-11
2 – #41 – #6
40,000 18-3 15-8 13-44 12-8 11-8 10-10 10-3 9-8 9-360,000 16-8 15-2 14-0 13-0 12-3 11-4 10-3
2 – #5 40,000 17-0 15-5 14-3 13-3 11-9 10-7 9-7Center distance A11,12 6-9 4-11 3-11 3-2 2-9 2-4 2-1 2-0 2-0
20
Span without stirrups9,10 8-10 6-5 5-1 4-2 3-6 3-1 2-9 2-5 2-3
1 – #440,000 15-2 13-0 11-6 10-5 9-7 9-0 8-5 8-0 7-760,000 18-6 15-9 14-0 12-8- 11-8 10-11 10-3 9-9 9-3
1 – #540,000 18-10 16-1 14-3 12-11 11-11 11-1 10-6 9-11 9-560,000 19-5 17-3 15-8 14-5 13-5 12-8 12-0 11-5
2 – #41 – #6
40,000 18-1 16-0 14-6 13-5 12-6 11-9 11-2 10-760,000 19-4 17-6 16-2 15-1 14-2 13-5 12-9
2 – #540,000 19-8 17-10 16-5 14-10 13-1 11-9 10-860,000 18-4 16-4 14-8 13-3
2 – #6 40,000 20-0 17-0 14-10 13-1 11-9 10-8Center distance A11,12 8-10 6-5 5-1 4-2 3-6 3-1 2-9 2-5 2-3
24
Span without stirrups9,10 11-1 8-0 6-3 5-2 4-4 3-10 3-4 3-0 2-9
1 – #440,000 17-1 14-6 12-10 11-8 10-9 10-0 9-5 8-11 8-660,000 20-9 17-8 15-7 14-2 13-1 12-2 11-5 10-10 10-4
1 – #540,000 18-0 15-11 14-5 13-4 12-5 11-8 11-0 10-660,000 19-4 17-6 16-2 15-0 14-2 13-5 12-9
2 – #41 – #6
40,000 20-3 17-11 16-3 15-0 13-11 13-1 12-5 11-860,000 18-1 16-10 15-10 15-0 14-3
2 – #540,000 18-5 16-4 14-5 12-11 11-860,000 18-3 16-4 14-10
2 – #6 40,000 18-9 16-4 14-5 12-11 11-8Center distance A11,12 11-1 8-0 6-3 5-2 4-4 3-10 3-4 3-0 2-9
For SI: 1 inch = 25.4 mm; 1 plf = 0.0146 kN/m; 1 ft = 0.3048 m; Grade 40 = 280 MPa; Grade 60 = 420 MPa
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Chapter 7 – Requirements for Lintels and Reinforcement Around Openings
Notes for Tables 7.19 through 7.221 See Table 2.1 for tolerances permitted from nominal thickness.2 Table values are based on concrete with a minimum specified compressive strength of 2,500 psi (17.2 MPa). See notes 10 and 12.3 Table values are based on uniform loading. See Section 7.2 for lintels supporting concentrated loads. 4 Deflection criterion is L/240, where L is the clear span of the lintel in inches, or 1⁄2-inch (13 mm), whichever is less.5 Linear interpolation is permitted between roof uplift forces and between lintel depths.6 The maximum clear span of a lintel shall not exceed 18 feet (5.5 m). Tabular values greater than 18 feet (5.5 m) are provided for purposes of inter-
polation.7 Lintel depth, D, is permitted to include the available height of wall located directly above the lintel, provided that the increased lintel depth
spans the entire length of the lintel.8 Stirrups shall be fabricated from reinforcing bars with the same yield strength as that used for the main longitudinal reinforcement.9 Allowable clear span without stirrups applicable to all lintels of the same depth, D. Top and bottom reinforcement for lintels without stirrups
shall not be less than the least amount of reinforcement required for a lintel of the same depth and loading condition with stirrups. All otherspans require stirrups spaced at not more than d/2.
10 Where concrete with a minimum specified compressive strength of 3,000 psi (20.7 MPa) is used, clear spans for lintels without stirrups shall bepermitted to be multiplied by 1.05. If the increased span exceeds the allowable clear span for a lintel of the same depth and loading conditionwith stirrups, the top and bottom reinforcement shall be equal to or greater than that required for a lintel of the same depth and loading condi-tion that has an allowable clear span that is equal to or greater than that of the lintel without stirrups that has been increased.
11 Center distance, A, is the center portion of the span where stirrups are not required. This is applicable to all longitudinal bar sizes and steel yieldstrengths.
12 Center distance, A, shall be permitted to be multiplied by 1.10 where concrete with a minimum specified compressive strength of 3,000 psi (20.7MPa) is used.
13 The maximum clear opening width between two solid wall segments shall be 18 feet (5.5 m). See Section 5.2.1. Lintel spans in table greater than18 feet (5.5 m) are shown for interpretation and informational purposes only.
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Table 7.20. Maximum Allowable Clear Spans for 6-inch Nominal Thick Flat Lintels in Top Story Walls Subject to Roof Uplift Forces1,2,3,4,5,6,13
For SI: 1 inch = 25.4 mm; 1 plf = 0.0146 kN/m; 1 ft = 0.3048 m; Grade 40 = 280 MPa; Grade 60 = 420 MPaLintels without stirrups shown in shaded cells shall have top and bottom reinforcement from this table that permits a lintel with stirrups of thesame depth and loading condition to have a clear span that is equal to or greater than the span of the lintel without stirrups.See Page 7-27 for additional notes.
LintelDepth7, D
(in.)
Number of barsand bar sizein top and
bottom of lintel
Steel yieldstrength8,
fy (psi)
Factored roof uplift force from Table 7.1A (plf)
600 800 1000 1200 1400 1600 1800 2000 2200
Maximum clear span of lintel for uplift forces (ft-inches)
8
Span without stirrups9,10 8-10 6-6 5-2 4-3 3-8 3-2 2-10 2-6 2-3
1 – #440,000 8-6 7-3 6-6 5-11 5-5 5-1 4-9 4-6 4-460,000 10-3 8-9 7-10 7-1 6-7 6-1 5-9 5-5 5-2
1 – #540,000 10-5 8-11 7-11 7-3 6-8 6-3 5-10 5-7 5-360,000 12-5 10-8 9-6 8-8 8-0 7-5 7-0 6-8 6-4
2 – #41 – #6 40,000 11-7 10-0 8-10 8-1 7-5 6-11 6-6 6-2 5-11
Center distance A11,12 8-10 6-6 5-2 4-3 3-8 3-2 2-10 2-6 2-3
12
Span without stirrups9,10 7-8 5-7 4-5 3-7 3-1 2-8 2-4 2-2 2-0
1 – #440,000 11-3 9-7 8-6 7-9 7-2 6-8 6-3 5-11 5-860,000 13-8 11-8 10-4 9-5 8-8 8-1 7-7 7-3 6-10
1 – #540,000 13-11 11-11 10-7 9-7 8-10 8-3 7-9 7-4 7-060,000 16-10 14-5 12-9 11-7 10-8 10-0 9-4 8-10 8-5
2 – #41 – #6
40,000 15-8 13-4 11-10 10-9 9-11 9-3 8-9 8-3 7-1060,000 18-10 16-1 14-3 12-11 11-11 11-2 10-6 9-11 9-5
2 – #540,000 19-2 16-4 14-6 13-2 12-2 11-4 10-8 10-1 9-760,000 19-5 17-3 15-8 14-5 13-6 12-8 12-0 11--5
2 – #6 40,000 19-2 17-0 15-5 14-2 13-3 12-4 11-1 10-1Center distance A11,12 7-8 5-7 4-5 3-7 3-1 2-8 2-4 2-2 1-11
16
Span without stirrups9,10 11-2 8-1 6-3 5-2 4-5 3-10 3-4 3-0 2-9
1 – #440,000 13-8 11-7 10-3 9-4 8-7 8-0 7-6 7-1 6-960,000 16-8 14-1 12-6 11-4 10-5 9-9 9-2 8-8 8-3
1 – #540,000 17-0 14-5 12-9 11-6 10-8 9-11 9-4 8-10 8-560,000 20-7 17-6 15-5 14-0 12-11 12-0 11-3 10-8 10-2
2 – #41 – #6
40,000 19-1 16-3 14-4 13-0 12-0 11-2 10-6 9-11 9-560,000 19-7 17-4 15-8 14-6 13-6 12-8 12-0 11-5
2 – #540,000 20-0 17-8 16-0 14-9 13-9 12-11 12-3 11-760,000 19-2 17-8 16-6 15-6 14-8 13-11
2 – #6 40,000 18-10 17-4 16-2 14-5 12-11 11-9Center distance A11,12 11-2 8-1 6-3 5-2 4-5 3-10 3-4 3-0 2-9
20
Span without stirrups9,10 14-11 10-8 8-3 6-9 5-9 5-0 4-5 3-11 3-6
1 – #540,000 19-9 16-8 14-8 13-3 12-2 11-4 10-8 10-1 9-760,000 20-3 17-10 16-1 14-10 13-10 13-0 12-3 11-8
2 – #41 – #6
40,000 18-9 16-6 14-11 13-9 12-9 12-0 11-4 10-1060,000 18-1 16--8 15-6 14-7 13-9 13-1
2 – #540,000 18-6 17-0 15-10 14-10 14-1 13-460,000 19-1 17-11 16-11 16-1
2 – #640,000 18-9 16-7 14-10 13-560,000 18-4 16-7
Center distance A11,12 14-11 10-8 8-3 6-9 5-9 5-0 4-5 3-11 3-6
24
Span without stirrups9,10 19-1 13-5 10-4 8-5 7-1 6-2 5-5 4-10 4-4
1 – #540,000 22-4 18-9 16-5 14-10 13-8 12-8 11-11 11-3 10-860,000 18-1 16-7 15-5 14-6 13-8 13-0
2 – #41 – #6
40,000 18-7 16-9 15-4 14-3 13-5 12-8 12-160,000 18-8 17-4 16-4 15-5 14-8
2 – #5 40,000 19-0 17-9 16-7 15-8 14-112 – #6 40,000 18-9 16-9 15-2Center distance A11,12 19-1 13-5 10-4 8-5 7-1 6-2 5-5 4-10 4-4
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Chapter 7 – Requirements for Lintels and Reinforcement Around Openings
Table 7.21. Maximum Allowable Clear Spans for 8-inch Nominal Thick Flat Lintels in Top Story Walls Subject to Roof Uplift Forces1,2,3,4,5,6,13
For SI: 1 inch = 25.4 mm; 1 plf = 0.0146 kN/m; 1 ft = 0.3048 m; Grade 40 = 280 MPa; Grade 60 = 420 MPaLintels without stirrups shown in shaded cells shall have top and bottom reinforcement from this table that permits a lintel with stirrups of thesame depth and loading condition to have a clear span that is equal to or greater than the span of the lintel without stirrups. See Page 7-27 for additional notes.
LintelDepth7, D
(in.)
Number of barsand bar sizein top and
bottom of lintel
Steel yieldstrength8,
fy (psi)
Factored roof uplift force from Table 7.1A (plf)
600 800 1000 1200 1400 1600 1800 2000 2200
Maximum clear span of lintel for uplift forces (ft-inches)
8
Span without stirrups9,10 12-5 9-1 7-2 5-11 5-0 4-4 3-10 3-6 3-2
1 – #440,000 8-8 7-5 6-7 6-0 5-6 5-2 4-10 4-7 4-460,000 10-6 9-0 7-11 7-3 6-8 6-3 5-10 5-6 5-3
1 – #540,000 10-8 9-2 8-1 7-4 6-9 6-4 6-0 5-8 5-560,000 12-10 11-0 9-9 8-10 8-2 7-8 7-2 6-10 6-6
2 – #41 – #6
40,000 12-0 10-3 9-1 8-3 7-7 7-1 6-8 6-4 6-060,000 14-4 12-3 10-10 9-11 9-1 8-6 8-0 7-7 7-3
2 – #5 40,000 14-7 12-6 11-1 10-1 9-3 8-8 8-2 7-9 7-4Center distance A11,12 12-5 9-1 7-2 5-11 5-0 4-4 3-10 3-6 3-2
12
Span without stirrups9,10 10-11 7-10 6-2 5-0 4-3 3-9 3-3 2-11 2-8
1 – #440,000 11-7 9-10 8-8 7-10 7-3 6-9 6-4 6-0 5-960,000 14-1 11-11 10-7 9-7 8-10 8-3 7-9 7-4 6-11
1 – #540,000 14-4 12-2 10-9 9-9 9-0 8-4 7-10 7-5 7-160,000 17-5 14-9 13-1 11-10 10-11 10-2 9-6 9-0 8-7
2 – #41 – #6
40,000 16-2 13-8 12-1 11-0 10-1 9-5 8-10 8-5 8-060,000 19-6 16-7 14-8 13-3 12-3 11-5 10-8 10-2 9-8
2 – #540,000 19-11 16-11 14-11 13-6 12-5 11-7 10-11 10-4 9-1060,000 20-3 17-11 16-3 14-11 13-11 13-1 12-4 11-9
2 – #6 40,000 19-11 17-7 15-11 14-8 13-8 12-10 12-2 11-7Center distance A11,12 10-11 7-10 6-2 5-0 4-3 3-9 3-3 2-11 2-8
16
Span without stirrups9,10 16-2 11-5 8-10 7-3 6-1 5-3 4-8 4-2 3-9
1 – #440,000 14-1 11-11 10-6 9-5 8-8 8-1 7-7 7-2 6-1060,000 17-3 14-6 12-9 11-6 10-7 9-10 9-3 8-9 8-4
1 – #540,000 17-7 14-9 13-0 11-9 10-10 10-1 9-5 8-11 8-660,000 21-4 18-0 15-10 14-4 13-2 12-3 11-6 10-10 10-4
2 – #41 – #6
40,000 19-9 16-8 14-8 13-3 12-2 11-4 10-8 10-1 9-760,000 20-3 17-10 16-1 14-9 13-9 12-11 12-3 11-7
2 – #540,000 18-2 16-5 15-1 14-0 13-2 12-5 11-1060,000 18-2 16-11 15-11 15-0 14-3
2 – #640,000 19-5 17-10 16-7 15-7 14-9 13-1160,000 18-8 17-8 16-9
Center distance A11,12 16-2 11-5 8-10 7-3 6-1 5-3 4-8 4-2 3-9
20
Span without stirrups9,10 22-0 15-4 11-9 9-7 8-0 6-11 6-1 5-5 4-11
1 – #540,000 20-7 17-2 15-1 13-7 12-5 11-7 10-10 10-3 9-960,000 20-11 18-4 16-6 15-2 14-1 13-2 12-6 11-10
2 – #41 – #6
40,000 19-4 17-0 15-3 14-0 13-0 12-3 11-6 11-060,000 18-7 17-0 15-10 14-10 14-0 13-4
2 – #540,000 18-11 17-5 16-2 15-2 14-4 13-760,000 18-4 17-4 16-6
2 – #6 40,000 19-2 18-0 17-0 16-2Center distance A11,12 22-0 15-4 11-9 9-7 8-0 6-11 6-1 5-5 4-11
24
Span without stirrups9,10 19-7 14-11 12-0 10-1 8-8 7-7 6-9 6-1
1 – #540,000 19-5 16-11 15-3 13-11 12-11 12-1 11-5 10-1060,000 18-7 17-0 15-9 14-9 13-11 13-3
2 – #41 – #6
40,000 19-2 17-2 15-9 14-7 13-8 12-11 12-360,000 19-2 17-9 16-7 15-8 14-11
2 – #5 40,000 18-1 17-0 16-0 15-2Center distance A11,12 19-7 14-11 12-0 10-1 8-8 7-7 6-9 6-1
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Table 7.22. Maximum Allowable Clear Spans for 10-inch Nominal Thick Flat Lintels in Top Story Walls Subject to Roof UpliftForces1,2,3,4,5,6,13
LintelDepth7, D
(in.)
Number of barsand bar sizein top and
bottom of lintel
Steel yieldstrength8,
fy (psi)
Factored roof uplift force from Table 7.1A (plf)
600 800 1000 1200 1400 1600 1800 2000 2200
Maximum clear span of lintel for uplift forces (ft-inches)
8
Span without stirrups9,10 16-2 11-9 9-3 7-7 6-5 5-7 4-11 4-5 4-0
1 – #440,000 8-10 7-6 6-8 6-0 5-7 5-2 4-10 4-7 4-560,000 10-8 9-1 8-1 7-4 6-9 6-3 5-11 5-7 5-4
1 – #540,000 10-11 9-3 8-3 7-6 6-11 6-5 6-0 5-9 5-560,000 13-2 11-3 9-11 9-0 8-4 7-9 7-3 6-11 6-7
2 – #41 – #6
40,000 12-3 10-5 9-3 8-5 7-9 7-2 6-9 6-5 6-160,000 14-9 12-7 11-1 10-1 9-4 8-8 8-2 7-9 7-4
2 – #540,000 15-0 12-9 11-4 10-3 9-6 8-10 8-4 7-10 7-660,000 17-10 15-3 13-6 12-3 11-3 10-6 9-11 9-4 8-11
Center distance A11,12 16-2 11-9 9-3 7-7 6-5 5-7 4-11 4-5 4-0
12
Span without stirrups9,10 14-5 10-3 8-0 6-6 5-6 4-9 4-3 3-9 3-5
1 – #440,000 11-10 10-0 8-10 8-0 7-4 6-10 6-5 6-1 5-960,000 14-5 12-2 10-9 9-8 8-11 8-4 7-10 7-4 7-0
1 – #540,000 14-9 12-5 10-11 9-11 9-1 8-6 7-11 7-6 7-260,000 17-11 15-1 13-4 12-0 11-1 10-3 9-8 9-2 8-8
2 – #41 – #6
40,000 16-7 14-0 12-4 11-2 10-3 9-6 9-0 8-6 8-160,000 20-1 17-0 14-11 13-6 12-5 11-7 10-10 10-3 9-9
2 – #540,000 20-6 17-4 15-3 13-9 12-8 11-9 11-1 10-6 10-060,000 18-4 16-7 15-3 14-2 13-4 12-7 12-0
2 – #640,000 18-0 16-3 15-0 13-11 13-1 12-5 11-960,000 19-6 17-11 16-8 15-8 14-10 14-1
Center distance A11,12 14-5 10-3 8-0 6-6 5-6 4-9 4-3 3-9 3-5
16
Span without stirrups9,10 21-10 15-2 11-8 9-5 7-11 6-10 6-0 5-4 4-10
1 – #440,000 14-7 12-2 10-8 9-7 8-10 8-2 7-8 7-3 6-1160,000 17-10 14-10 13-0 11-9 10-9 10-0 9-4 8-10 8-5
1 – #540,000 18-2 15-2 13-3 12-0 11-0 10-2 9-7 9-0 8-760,000 18-6 16-2 14-7 13-4 12-5 11-8 11-0 10-5
2 – #41 – #6
40,000 20-6 17-1 15-0 13-6 12-4 11-6 10-9 10-2 9-860,000 18-3 16-5 15-0 14-0 13-1 12-5 11-9
2 – #540,000 18-7 16-9 15-4 14-3 13-4 12-7 12-060,000 18-7 17-3 16-2 15-3 14-6
2 – #640,000 18-3 16-11 15-10 15-0 14-360,000 18-1 17-2
Center distance A11,12 21-10 15-2 11-8 9-5 7-11 6-10 6-0 5-4 4-10
20
Span without stirrups9,10 20-7 15-7 12-7 10-6 9-0 7-11 7-0 6-4
1 – #540,000 21-6 17-9 15-5 13-10 12-8 11-9 11-0 10-4 9-1060,000 18-10 16-10 15-5 14-4 13-5 12-8 12-0
2 – #41 – #6
40,000 20-0 17-5 15-7 14-3 13-3 12-5 11-8 11-160,000 19-0 17-5 16-1 15-1 14-3 13-6
2 – #540,000 19-5 17-9 16-5 15-5 14-6 13-960,000 18-8 17-8 16-9
2 – #6 40,000 18-4 17-3 16-5Center distance A11,12 20-7 15-7 12-7 10-6 9-0 7-11 7-0 6-4
24
Span without stirrups9,10 19-11 15-11 13-3 11-4 9-11 8-9 7-11
1 – #540,000 20-3 17-6 15-7 14-3 13-2 12-3 11-7 11-060,000 19-0 17-4 16-1 15-0 14-2 13-5
2 – #41 – #6
40,000 19-9 17-7 16-1 14-10 13-11 13-1 12-560,000 18-1 16-11 15-11 15-1
2 – #540,000 18-6 17-3 16-3 15-560,000 18-9
Center distance A11,12 19-11 15-11 13-3 11-4 9-11 8-9 7-11
For SI: 1 inch = 25.4 mm; 1 plf = 0.0146 kN/m; 1 ft = 0.3048 m; Grade 40 = 280 MPa; Grade 60 = 420 MPaLintels without stirrups shown in shaded cells shall have top and bottom reinforcement from this table that permits a lintel with stirrups of thesame depth and loading condition to have a clear span that is equal to or greater than the span of the lintel without stirrups. See Page 7-27 for additional notes.
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Chapter 7 – Requirements for Lintels and Reinforcement Around Openings
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7-32
Table 7.23. Maximum Allowable Clear Spans for 6-inch Thick Waffle-Grid Lintels in Top Story Walls Subject toRoof Uplift Forces1,2,3,4,5,6,15
LintelDepth7, D
(in.)
Number of barsand bar sizein top and
bottom of lintel
Steel yieldstrength8,
fy (psi)
Factored roof uplift force from Table 7.1A (plf)
600 800 1000 1200 1400 1600 1800 2000 2200
Maximum clear span of lintel for uplift forces (ft-inches)
89
Span without stirrups11,12 4-2 3-1 2-5 2-0 2-0 2-0 2-0 2-0 2-0
1 – #440,000 8-5 7-3 6-5 5-10 5-2 4-6 4-0 3-7 3-3
60,000 10-1 8-8 7-3 6-0 5-2 4-6 4-0 3-7 3-3
1 – #540,000 10-3 8-10 7-3 6-0 5-2 4-6 4-0 3-7 3-3
60,000 12-3 9-2 7-3 6-0 5-2 4-6 4-0 3-7 3-3
Center distance A13,14 4-2 3-1 2-5 2-0 2-0 2-0 2-0 2-0 2-0
129
Span without stirrups11,12 3-7 2-7 2-1 2-0 2-0 2-0 2-0 2-0 2-0
1 – #440,000 9-8 8-3 7-4 6-8 6-2 5-9 5-5 5-2 4-11
60,000 13-6 11-7 10-3 9-4 8-7 7-7 6-8 6-0 5-5
1 – #540,000 13-9 11-9 10-6 9-6 8-8 7-7 6-8 6-0 5-5
60,000 16-7 14-3 12-4 10-2 8-8 7-7 6-8 6-0 5-5
2 – #41 – #6
40,000 15-5 13-3 11-9 10-2 8-8 7-7 6-8 6-0 5-5
60,000 18-6 15-7 12-4 10-2 8-8 7-7 6-8 6-0 5-5
Center distance A13,14 3-7 2-7 2-1 2-0 2-0 2-0 2-0 2-0 2-0
169
Span without stirrups11,12 5-1 3-9 2-11 2-5 2-1 2-0 2-0 2-0 2-0
1 – #440,000 11-8 10-0 8-10 8-0 7-5 6-11 6-6 6-2 5-10
60,000 14-3 12-2 10-9 9-9 9-0 8-5 7-11 7-6 7-1
1 – #540,000 14-6 12-5 11-0 10-0 9-2 8-7 8-1 7-8 7-3
60,000 20-3 17-3 15-3 13-10 12-3 10-8 9-5 8-6 7-8
2 – #41 – #6
40,000 18-9 16-0 14-2 12-10 11-10 10-8 9-5 8-6 7-8
60,000 19-4 17-1 14-6 12-3 10-8 9-5 8-6 7-8
2 – #5 40,000 19-8 17-5 14-6 12-3 10-8 9-5 8-6 7-8
Center distance A13,14 5-1 3-9 2-11 2-5 2-1 2-0 2-0 2-0 2-0
209
Span without stirrups11,12 6-10 4-11 3-10 3-2 2-8 2-4 2-1 2-0 2-0
1 – #440,000 13-6 11-6 10-2 9-2 8-5 7-10 7-5 7-0 6-8
60,000 16-6 14-0 12-4 11-2 10-4 9-7 9-0 8-6 8-2
1 – #540,000 16-9 14-3 12-7 11-5 10-6 9-10 9-3 8-9 8-3
60,000 19-11 17-7 15-11 14-8 13-8 12-3 11-0 9-11
2 – #41 – #6
40,000 18-11 16-1 14-3 12-10 11-10 11-1 10-5 9-10 9-4
60,000 19-9 17-11 16-0 13-11 12-3 11-0 9-11
2 – #5 40,000 18-2 15-5 13-4 11-10 10-7 9-7
Center distance A13,14 6-10 4-11 3-10 3-2 2-8 2-4 2-1 2-0 2-0
2410
Span without stirrups11,12 8-7 6-2 4-9 3-11 3-4 2-10 2-6 2-3 2-0
1 – #440,000 15-2 12-10 11-4 10-3 9-5 8-9 8-3 7-9 7-5
60,000 18-6 15-8 13-10 12-6 11-6 10-8 10-1 9-6 9-0
1 – #540,000 18-11 16-0 14-1 12-9 11-9 10-11 10-3 9-8 9-3
60,000 19-6 17-2 15-6 14-3 13-4 12-6 11-10 11-3
2 – #41 – #6
40,000 18-0 15-11 14-5 13-3 12-4 11-7 10-11 10-5
60,000 18-6 17-2 15-2 13-7 12-3
2 – #5 40,000 19-10 16-10 14-7 12-10 11-6 10-5
Center distance A13,14 8-7 6-2 4-9 3-11 3-4 2-10 2-6 2-3 2-0
For SI: 1 inch = 25.4 mm; 1 plf = 0.0146 kN/m; 1 ft = 0.3048 m
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Chapter 7 – Requirements for Lintels and Reinforcement Around Openings
Notes for Tables 7.23 and 7.241 Where lintels are formed with waffle-grid forms, form material shall be removed, if necessary, to create top and bottom flanges of the lintel that
are not less than 3 inches (76 mm) in depth (in the vertical direction), and are not less than 5 inches (127 mm) in width for 6-inch (152 mm) nominalwaffle-grid forms and not less than 7 inches (178 mm) in width for 8-inch (203 mm) nominal waffle-grid forms. See Figure 7.4. Flat stay-in-placeform lintels shall be permitted to be used in lieu of waffle-grid lintels. See Tables 7.3 through 7.10.
2 See Table 2.1 for tolerances permitted from nominal thicknesses and minimum dimensions and spacing of cores.3 Table values are based on concrete with a minimum specified compressive strength of 2,500 psi (17.2 MPa). See notes 12 and 14. Table values
are based on uniform loading. See Section 7.2 for lintels supporting concentrated loads. 4 Deflection criterion is L/240, where L is the clear span of the lintel in inches, or 1⁄2-inch (13 mm), whichever is less.5 Interpolation is permitted between roof uplift forces.6 The maximum clear span of a lintel shall not exceed 18 feet (5.5 m). Tabular values greater than 18 feet (5.5 m) are provided for purposes of inter-
polation.7 Lintel depth, D, is permitted to include the available height of wall located directly above the lintel, provided that the increased lintel depth
spans the entire length of the lintel.8 Stirrups shall be fabricated from reinforcing bars with the same yield strength as that used for the main longitudinal reinforcement.9 Lintels less than 24 inches (610 mm) in depth with stirrups shall be formed from flat-walls forms (see Tables 7.3 through 7.10), or, if necessary,
form material shall be removed from waffle-grid forms so as to provide the required cover for stirrups. Allowable spans for lintels formed withflat-wall forms shall be determined from Tables 7.3 through 7.10.
10 Where stirrups are required for 24-inch (610 mm) deep lintels, the spacing shall not exceed 12 inches (305 mm) on center. 11 Allowable clear span without stirrups applicable to all lintels of the same depth, D. Top and bottom reinforcement for lintels without stirrups
shall not be less than the least amount of reinforcement required for a lintel of the same depth and loading condition with stirrups. All otherspans require stirrups spaced at not more than d/2.
12 Where concrete with a minimum specified compressive strength of 3,000 psi (20.7 MPa) is used, clear spans for lintels without stirrups shall bepermitted to be multiplied by 1.05. If the increased span exceeds the allowable clear span for a lintel of the same depth and loading conditionwith stirrups, the top and bottom reinforcement shall be equal to or greater than that required for a lintel of the same depth and loading condi-tion that has an allowable clear span that is equal to or greater than that of the lintel without stirrups that has been increased.
13 Center distance, A, is the center portion of the span where stirrups are not required. This is applicable to all longitudinal bar sizes and steel yieldstrengths.
14 Where concrete with a minimum specified compressive strength of 3,000 psi (20.7 MPa) is used, center distance, A, shall be permitted to be multi-plied by 1.10.
15 The maximum clear opening width between two solid wall segments shall be 18 feet (5.5 m). See Section 5.2.1. Lintel spans in table greater than18 feet (5.5 m) are shown for interpolation and information purposes only.
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7-34
Table 7.24. Maximum Allowable Clear Spans for 8-inch Thick Waffle-Grid Lintels in Top Story Walls Subject toRoof Uplift Forces1,2,3,4,5,6,15
LintelDepth7, D
(in.)
Number of barsand bar sizein top and
bottom of lintel
Steel yieldstrength8,
fy (psi)
Factored roof uplift force from Table 7.1A (plf)
600 800 1000 1200 1400 1600 1800 2000 2200
Maximum clear span of lintel for uplift forces (ft-inches)
89
Span without stirrups11,12 4-3 3-1 2-5 2-0 2-0 2-0 2-0 2-0 2-0
1 – #440,000 7-5 6-5 5-8 5-2 4-9 4-5 4-0 3-7 3-3
60,000 10-4 8-10 7-4 6-1 5-2 4-6 4-0 3-7 3-3
1 – #540,000 10-7 9-0 7-4 6-1 5-2 4-6 4-0 3-7 3-3
60,000 12-8 9-4 7-4 6-1 5-2 4-6 4-0 3-7 3-3
Center distance A13,14 4-3 3-1 2-5 2-0 2-0 2-0 2-0 2-0 2-0
129
Span without stirrups11,12 3-8 2-8 2-1 2-0 2-0 2-0 2-0 2-0 2-0
1 – #440,000 9-11 8-5 7-6 6-9 6-3 5-10 5-6 5-2 4-11
60,000 12-1 10-3 9-1 8-3 7-7 7-1 6-8 6-1 5-6
1 – #540,000 12-3 10-6 9-3 8-5 7-9 7-3 6-9 6-1 5-6
60,000 17-1 14-7 12-7 10-4 8-9 7-8 6-9 6-1 5-6
2 – #41 – #6
40,000 15-10 13-6 12-0 10-4 8-9 7-8 6-9 6-1 5-6
60,000 19-2 16-0 12-7 10-4 8-9 7-8 6-9 6-1 5-6
Center distance A13,14 3-8 2-8 2-1 2-0 2-0 2-0 2-0 2-0 2-0
169
Span without stirrups11,12 5-4 3-10 3-0 2-6 2-1 2-0 2-0 2-0 2-0
1 – #440,000 12-0 10-2 9-0 8-1 7-6 7-0 6-6 6-2 5-11
60,000 14-8 12-5 10-11 9-11 9-1 8-6 8-0 7-7 7-2
1 – #540,000 14-11 12-8 11-2 10-1 9-4 8-8 8-2 7-9 7-4
60,000 18-2 15-5 13-7 12-4 11-4 10-7 9-7 8-7 7-9
2 – #41 – #6
40,000 16-10 14-3 12-7 11-5 10-6 9-9 9-2 8-7 7-9
60,000 19-11 17-7 14-9 12-6 10-10 9-7 8-7 7-9
2 – #540,000 20-3 17-11 14-9 12-6 10-10 9-7 8-7 7-9
60,000 23-1 18-0 14-9 12-6 10-10 9-7 8-7 7-9
Center distance A13,14 5-4 3-10 3-0 2-6 2-1 2-0 2-0 2-0 2-0
209
Span without stirrups11,12 7-3 5-1 4-0 3-3 2-9 2-4 2-1 2-0 2-0
1 – #440,000 13-11 11-9 10-4 9-4 8-7 8-0 7-6 7-1 6-9
60,000 17-0 14-4 12-7 11-5 10-6 9-9 9-2 8-8 8-3
1 – #540,000 17-4 14-7 12-10 11-7 10-8 9-11 9-4 8-10 8-5
60,000 21-2 17-10 15-8 14-2 13-0 12-1 11-4 10-9 10-1
2 – #41 – #6
40,000 19-7 16-6 14-6 13-1 12-1 11-3 10-6 9-11 9-6
60,000 20-1 17-8 16-0 14-8 13-8 12-6 11-2 10-1
2 – #540,000 18-0 16-3 15-0 13-8 12-0 10-9 9-9
60,000 19-5 16-5 14-2 12-6 11-2 10-1
Center distance A13,14 7-3 5-1 4-0 3-3 2-9 2-4 2-1 2-0 2-0
2410
Span without stirrups11,12 9-3 6-6 5-0 4-0 3-5 2-11 2-7 2-4 2-1
1 – #440,000 15-10 13-2 11-7 10-5 9-7 8-11 8-4 7-11 7-6
60,000 19-4 16-2 14-2 12-9 11-8 10-10 10-2 9-7 9-2
1 – #540,000 19-8 16-6 14-5 13-0 11-11 11-1 10-5 9-10 9-4
60,000 20-1 17-7 15-10 14-7 13-6 12-8 12-0 11-5
2 – #41 – #6
40,000 18-7 16-3 14-8 13-6 12-6 11-9 11-1 10-6
60,000 19-10 17-11 16-5 15-3 14-4 13-6 12-6
2 – #540,000 18-3 16-9 14-11 13-2 11-9 10-7
60,000 20-5 17-7 15-6 13-10 12-6
Center distance A13,14 9-3 6-6 5-0 4-0 3-5 2-11 2-7 2-4 2-1
For SI: 1 inch = 25.4 mm; 1 plf = 0.0146 kN/m; 1 ft = 0.3048 mSee Page 7-33 for notes.
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Chapter 7 – Requirements for Lintels and Reinforcement Around Openings
Table 7.25. Maximum Allowable Clear Spans for 6-inch Thick Screen-Grid Lintels in Top Story Walls Subject toRoof Uplift Forces1,2,3,4,5,6
LintelDepth7, D
(in.)
Number of barsand bar sizein top and
bottom of lintel
Steel yieldstrength8,
fy (psi)
Factored roof uplift force from Table 7.1A (plf)
600 800 1000 1200 1400 1600 1800 2000 2200
Maximum clear span of lintel for uplift forces (ft-inches)
129,10 Span without stirrups13 3-0 2-2 2-0 2-0 2-0 2-0 2-0 2-0 2-0
169,10 Span without stirrups13 4-4 3-2 2-6 2-0 2-0 2-0 2-0 2-0 2-0
209,10 Span without stirrups13 5-9 4-1 3-3 2-8 2-3 2-0 2-0 2-0 2-0
2411
Span without stirrups12,13 7-2 5-2 4-0 3-3 2-9 2-5 2-2 2-0 2-0
1 – #440,000 15-1 12-9 11-3 10-3 9-5 8-9 8-3 7-9 7-5
60,000 18-5 15-7 13-9 12-6 11-6 10-8 10-0 9-6 9-0
1 – #540,000 18-10 15-11 14-1 12-9 11-8 10-11 10-3 9-8 9-3
60,000 19-5 17-1 15-6 14-3 13-3 12-6 11-5 10-4
2 – #41 – #6
40,000 18-0 15-10 14-4 13-2 12-3 11-7 10-9 9-9
60,000 19-9 16-8 14-6 12-9 11-5 10-4
2 – #5 40,000 18-7 15-9 13-8 12-0 10-9 9-9
Center distance A14,15 7-2 5-2 4-0 3-3 2-9 2-5 2-2 2-0 2-0
For SI: 1 inch = 25.4 mm; 1 plf = 0.0146 kN/m; 1 ft = 0.3048 m1 Where lintels are formed with screen-grid forms, form material shall be removed if necessary to create top and bottom flanges of the lintel that
are not less than 5 inches (127 mm) in width and not less than 2.5 inches (64 mm) in depth (in the vertical direction). See Figure 7.5. Flat stay-in-place form lintels shall be permitted to be used in lieu of screen-grid lintels. See Tables 7.3 through 7.10.
2 See Table 2.1 for tolerances permitted from nominal thickness and minimum dimensions and spacings of cores.3 Table values are based on concrete with a minimum specified compressive strength of 2,500 psi (17.2 MPa). See notes 13 and 15. Table values
are based on uniform loading. See Section 7.2 for lintels supporting concentrated loads. 4 Deflection criterion is L/240, where L is the clear span of the lintel in inches, or 1⁄2-inch (13 mm), whichever is less.5 Linear interpolation is permitted between roof uplift forces.6 The maximum clear opening width between two solid wall segments shall be 18 feet (5.5 m). See Section 5.2.1. Lintel spans in table greater than
18 feet (5.5 m) are shown for interpolation and information purposes only.7 Lintel depth, D, is permitted to include the available height of wall located directly above the lintel, provided that the increased lintel depth
spans the entire length of the lintel.8 Stirrups shall be fabricated from reinforcing bars with the same yield strength as that used for the main longitudinal reinforcement.9 Stirups are not required for lintels less than 24 inches (610 mm) in depth fabricated from screen-grid forms. Top and bottom reinforcement shall
consist of a No. 4 bar having a minimum yield strength of 40,000 psi (280 MPa) or 60,000 psi (420 MPa). 10 Lintels between 12 (305) and 24 inches (610 mm) in depth with stirrups shall be formed from flat-walls forms (see Tables 7.3 through 7.10), or
form material shall be removed from screen-grid forms so as to provide a concrete section comparable to that required for a flat wall. Allowablespans for flat lintels with stirrups shall be determined from Tables 7.3 through 7.10.
11 Where stirrups are required for 24-inch (610 mm) deep lintels, the spacing shall not exceed 12 inches (305 mm) on center. 12 Allowable clear span without stirrups applicable to all lintels of the same depth, D. Top and bottom reinforcement for lintels without stirrups
shall not be less than the least amount of reinforcement required for a lintel of the same depth and loading condition with stirrups. All otherspans require stirrups spaced at not more than 12 inches (305 mm).
13 Where concrete with a minimum specified compressive strength of 3,000 psi (20.7 MPa) is used, spans for lintels without stirrups shall be permittedto be multiplied by 1.05.
14 Center distance, A, is the center portion of the span where stirrups are not required. This is applicable to all longitudinal bar sizes and steel yieldstrengths.
15 Where concrete with a minimum specified compressive strength of 3,000 psi (20.7 MPa) is used, center distance, A, shall be permitted to be multi-plied by 1.10.
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Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
7-36
See Figure 7.3,7.4 or 7.5
Wall reinforcementas required
* *
Flat and waffle-grid – 8" (203 mm) min.Screen-grid – 12" (305 mm) min.
Top ofwall story
Center distance, A,not requiring stirrups
Top and bottomlintel reinforcementas required – SeeSection 7.2
See Section 7.1
opening reinforcementas required
Elevation of Wall
A
Vertical reinforcement beside opening.See Section 7.1.2
< 2'
(610 mm)> 2'
(610 mm)
Continuous bar as required by Chapter3 or 4 shall be permitted to be usedas lintel reinforcement where locatedas shown in Figure 7.3, 7.4 or 7.5
* *
* Length required to develop bar in tension – See Section 7.1.1
Figure 7.1. Reinforcement around openings.
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Chapter 7 – Requirements for Lintels and Reinforcement Around Openings
CL of bar
d
b
Stirrup spacing
Lintel span
a b b
Vertical bars continuous or hooked todevelop bar in tension – see Section 2.5.4
Section A-A
Lintel Reinforcing
Less than
24" (610 mm)
a
b
b
b
a = d/4, but not more than 3" (76 mm)
b = d/2, but not more than 6" (152 mm)
Tie
spac
ing
Less than24" (610 mm)
Wall Segment Reinforcing
Top and bottom bars continuous, extendedminimum 24" (610 mm) past opening,
or hooked to develop bar in tension –see Section 2.5.4
A
A
A A
Figure 7.2. Lintel and wall segment reinforcing for Seismic Design Categories C, D0, D1 and D2.
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Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
7-38
T11/2" (38 mm) minimum21/2" (64 mm) maximum
11/2" (38 mm) minimum21/2" (64 mm) maximum
dD d
Horizontal toplintel reinforcementas required*
Horizontal bottomlintel reinforcementas required*
Minimum No. 3stirrup as required.“C” stirrups areacceptable
Form – stay-in-placeor removable
Section Cut through Flat Wall Lintel
*For bundled bars, see Section 7.2.2.
Top
bar
Bot
tom
bar
135° hook forSeismic DesignCategory D0, D1 or D2
Figure 7.3. Flat lintel construction.
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Chapter 7 – Requirements for Lintels and Reinforcement Around Openings
T
(a) Single Form Height Section Cut through Vertical Core of a Waffle-Grid Lintel
Horizontal toplintel reinforcementas required*
Horizontal bottom lintel reinforcement as required*
Minimum No. 3stirrup as required.“C” stirrups areacceptable
Form – generallystay-in-place
Concrete web (hidden)
Vertical concrete core
T
(b) Double Form Height Section Cut through Vertical Core of a Waffle-Grid Lintel
*For bundled bars, see Section 7.2.2.
Note: Cross-hatching represents the area in which form material shall be removed, if necessary, to create flanges continuous the length of the lintel. Flanges shall have a minimum thickness of 3", and a minimum width of 5" and 7" in 6" nominal and 8" nominal waffle-grid walls, respectively.
Horizontal toplintel reinforcementas required*
Horizontal bottomlintel reinforcementas required*
Minimum No. 3stirrup as required.“C” stirrups areacceptable
Form – generallystay-in-place
Concrete web (hidden)
Vertical concrete core
11/2" (38 mm) minimum21/2" (64 mm) maximum
11/2" (38 mm) minimum21/2" (64 mm) maximum
dD d
Top
bar
Bot
tom
bar
11/2" (38 mm) minimum21/2" (64 mm) maximum
11/2" (38 mm) minimum21/2" (64 mm) maximum
dD d
Top
bar
Bot
tom
bar
135° hook forSeismic DesignCategory D0, D1 or D2
135° hook forSeismic DesignCategory D0, D1 or D2
Figure 7.4. Waffle-grid lintel construction.
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Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
7-40
T
(a) Single Form HeightSection Cut through Vertical Core
of a Screen-Grid Lintel
Horizontal toplintel reinforcementas required*
Form – generallystay-in-place
Horizontal concretecore (hidden)
Vertical concrete core
T
(b) Double Form HeightSection Cut through Vertical Core
of a Screen-Grid Lintel
*For bundled bars, see Section 7.2.2.
Horizontal toplintel reinforcementas required*
Horizontal bottom lintelreinforcement as required*
Minimum No. 3stirrup as required.“C” stirrups areacceptable
Form – generallystay-in-place
Horizontal concretecore (hidden)
Vertical concrete core
11/2" (38 mm) minimum21/2" (64 mm) maximum
11/2" (38 mm) minimum21/2" (64 mm) maximum
dD d
Top
bar
Bot
tom
bar
11/2" (38 mm) minimum21/2" (64 mm) maximum
11/2" (38 mm) minimum21/2" (64 mm) maximum
dD d
Top
bar
Bot
tom
bar
Horizontal bottom lintelreinforcement as required*
Note: Cross-hatching represents the area in which form material shall be removed, if necessary, to create flanges continuous the length of the lintel. Flanges shall have a minimum thickness of 2.5" and a minimum width of 5".
Figure 7.5. Screen-grid lintel construction.
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A-1
Appendix AASD Load Tables and Load Combinations forConcrete Wall Connections to Light-Framed Floor,Ceiling and Roof Systems
A.1 GENERALAppendix A load tables are provided to allow the design ofconnections or selection of proprietary connector devices, asan alternative to the connection details in Figures 6.3through 6.14. Connector devices shall be installed in accor-dance with the manufacturer’s installation instructions andapplicable requirements from evaluation reports.
For each connection detail, allowable stress design (ASD)load tables and load combinations are provided in thisappendix. Load and Resistance Factor Design (LRFD)(strength design) load tables and load combinations areprovided in Appendix B. The use of either ASD or LRFD loadsand load combinations is permitted, however mixing of ASDand LRFD is not permitted.
In order to use the Appendix A tables, the followinginformation must be identified:
1. Whether one or multiple connectors will be used
2. Connector spacing(s) (in)
3. The floor joist span perpendicular to the wall (ft)
4. Roof angle (degrees or rise to run)
5. Larger building plan dimension (ft)
6. Ratio of larger to smaller building plan dimension (roofand floor aspect ratio)
7. Basic wind speed (mph) and exposure category (B, C or D)
8. Seismic Design Category (SDC)
A.2 DETAIL 1 ASD LOAD TABLESFigure A.1 Detail 1 is for the connection of a two-storyconcrete wall to a light-framed floor system (floor dia-phragm) similar to the connection details of Figures 6.3through 6.6. Three loads act on this connection simultan-eously (Figure A.1). One connection device shall be capable
of resisting all three loads, or alternately two or moreconnection devices shall be permitted. Although Figure A.1depicts cold-formed steel framing members, the load combi-nations and tables in this section also apply to wood framingmembers.
DETAIL 1 ASD LOAD COMBINATIONSFor all buildings, connector devices shall be capable ofresisting not less than the following ASD load combinations:
1. VV1
2. VHW
3. TW3
4. VV4 + VHW + TW4
5. VV5 + 0.75 VHW + 0.75 TW5
Where VV1, VV4, VV5, VHW, TW3, TW4 and TW5 are deter-mined from Tables A1.1 through A1.3. In no case shallTW3, TW4 or TW5 be taken as less than 200 pounds perlinear foot (2.92 kN/m) times the anchor spacing.
TW or TS
VV
VHW or VHS(IN-PLANE)
Figure A.1. Detail 1 loads.
Appendix A is adopted by reference within Chapter 6 of the Standard;therefore, it is a mandatory part of the Standard.
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Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
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For multiple dwellings assigned to Seismic DesignCategory C, and all buildings assigned to Seismic DesignCategory D0, D1 or D2, connector devices shall also becapable of resisting the following additional ASD loadcombinations:
6. VHS
7. TS
8. VV8 + VHS + TS
9. VV9 + 0.75 VHS + 0.75 TS
Where VV8, VV9, VHS and TS are determined from TablesA1.1, A1.4 and A1.5. In no case shall TS be taken as lessthan 200 pounds per linear foot (2.92 kN/m) times theanchor spacing.
Selected connectors shall be capable of resisting theabove loads acting alone or in combination.
Table A1.1. VV (lb/conn ASD)3
Loading
Floor joist span perpendicular to wall (ft)1,2
12 16 20 24 28 32
VV1 Use in loadcombination 1 D+L
300 400 500 600 700 800
VV4, VV8 Use in loadcombinations 4 and 8 D
60 80 100 120 140 160
VV5, VV9 Use in loadcombinations 5 and 9 D + 0.75L
240 320 400 480 560 640
For SI: I in. = 25.4 mm; 1 ft. = 0.3048 m; I lb. = 4.448 N1 Interpolation between tabulated floor joist spans is permitted.2 For joists spanning parallel to the concrete wall, VV is permitted to be taken as zero.3 Tabulated loads are based on a connection spacing of 12 inches (305 mm). For other spacings, multiple value from tableby desired connection spacing in inches (mm) and divide by 12 (305).
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A-3
Appendix A
For SI: 1 in. = 25.4 mm; 1 ft. = 0.3048 m; 1 mph = 0.4470 m/s; 1 psf = 0.0479 kN/m2; I lb. = 4.448 N1 Tabulated loads are based on a diaphragm aspect ratio of 2 (ratio of larger plan dimension to smaller plan dimension).
Tabulated values are permitted to be reduced by multiplying by 0.50 for a diaphragm aspect ratio of 2 to 1. Interpolationbetween aspect ratios of 2 and 1 is permitted.
2 Tabulated loads are based on a wall floor-to-ceiling clear height of 10 feet (3.0 m) for the first and second stories. Loads arepermitted to be reduced by multiplying by 0.91 where the average wall floor-to-ceiling clear height of the first and secondstories does not exceed 9 feet (2.7 m).
3 For intermediate roof slopes use the larger tabulated value, or determine the value by interpolation.4 For intermediate larger building plan dimensions, use the value for the next smaller tabulated building dimension, or determine
by interpolation.5 Tabulated loads are based on a connection spacing of 12 inches (305 mm). For other spacings, multiple value from table by
desired connection spacing in inches (mm) and divide by 12 (305).
LoadingRoofslope
(angle)3
Largerbuilding plandimension
(ft)4
Basic wind speed (mph) and velocity pressure (psf)
85B 90B 100B 110B 120B 130B 140B 150B 166B 179B 192B
85C 90C 100C 110C 120C 130C 140C 150C 163C
85D 90D 100D 110D 120D 130D 140D 150D
11.51 12.9 15.95 19.28 22.94 26.92 31.79 37.41 43.9 50.91 58.45
VHWUse in loadcombinations2, 4 and 5
W
0:12to 1:12(0-5
degrees)
20 110 123 152 184 219 257 304 357 419 486 558
40 100 112 138 167 199 233 275 324 380 441 506
60 96 107 133 160 191 224 265 311 365 424 486
4.4:12(20
degrees)
20 153 171 211 256 304 357 421 496 582 675 775
40 138 155 192 232 276 324 382 450 528 612 703
60 133 149 184 223 265 311 368 433 508 589 676
7:12to 12:12(30-45degrees)
20 133 149 185 223 266 312 368 433 508 589 677
40 126 141 175 211 251 295 349 410 481 558 641
60 124 138 171 207 246 289 341 401 471 546 627
Table A1.2 Wind VHW (lb/conn ASD)1, 2, 5
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For SI: 1 in. = 25.4 mm; 1 mph = 0.4470 m/s; 1 psf = 0.0479 kN/m2; I lb. = 4.448 N1 Tabulated loads are based on a wall floor-to-ceiling clear height of 10 feet (3.0 m) for the first and second stories. Loads are
permitted to be reduced by multiplying by 0.91 where the average wall floor-to-ceiling clear height of the first and secondstories does not exceed 9 feet (2.7 m).
2 For intermediate roof slopes use the larger tabulated value, or determine the value by interpolation.3 Tabulated TW3 loads are permitted to be reduced by multiplying by 0.91 for roof slopes less than or equal to 10 degrees.4 Tabulated loads are based on a connection spacing of 12 inches (305 mm). For other spacings, multiple value from table by
desired connection spacing in inches (mm) and divide by 12 (305).
A-4
Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
LoadingRoofslope
(angle)2
Basic wind speed (mph) and velocity pressure (psf)
85B 90B 100B 110B 120B 130B 140B 150B 166B 179B 192B
85C 90C 100C 110C 120C 130C 140C 150C 163C
85D 90D 100D 110D 120D 130D 140D 150D
11.51 12.9 15.95 19.28 22.94 26.92 31.79 37.41 43.9 50.91 58.45
TW3 Use in loadcombination 3 W
components & cladding
All roofslopes
(angles)3162 182 225 271 323 379 448 527 618 717 823
TW4, TW5 Use in loadcombinations 4 and 5
W MWFRS
0:12 to 1:12(0-5 degrees) 60 67 82 100 119 139 164 193 227 263 302
4.4:12(20 degrees) 77 87 107 129 154 181 213 251 295 342 392
7:12 to 12:12(30-45 degrees) 70 78 96 117 139 163 192 226 266 308 354
Table A1.3 Wind TW (lb/conn ASD)1, 4
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A-5
Appendix A
For SI: 1 in. = 25.4 mm; 1 ft. = 0.3048 m; 1 psf = 0.479 kN/m2; I lb. = 4.448 N1 Tabulated loads are based on a wall floor-to-ceiling clear height of 10 feet (3.0 m) for the first and second stories. Loads are
permitted to be reduced by multiplying by 0.95 where the average wall floor-to-ceiling clear height of the first and secondstories does not exceed 9 feet (2.7 m).
2 Tabulated weight includes concrete weight only. 13 psf (0.62 kN/m2) additional weight is permitted for combined interior andexterior wall finishes. See Table 2.1 for weights of walls within the scope of this Standard.
3 Tabulated loads are based on a diaphragm aspect ratio of 2 (ratio of larger plan dimension to smaller plan dimension).Tabulated values are permitted to be reduced by multiplying by 0.60 for a diaphragm aspect ratio of 1. Interpolation betweenaspect ratios of 2 and 1 is permitted.
4 For intermediate larger building plan dimensions, use the value for the next larger tabulated building dimension, or determineby interpolation.
5 Interpolation between tabulated SDS values is permitted. For Seismic Design Category C, interpolation between 0.50 and thelower-bound threshold SDS value of 0.33 is permitted.
6 Tabulated loads are based on a connection spacing of 12 inches (305 mm). For other spacings, multiple value from table bydesired connection spacing in inches (mm) and divide by 12 (305).
LoadingMaximum
concrete wallweight (psf)2
Ratio of larger buildingplan dimension to smallerbuilding plan dimension3
Larger building plandimension (ft)4
Seismic design category andmaximum SDS value (g )5
C D0 D1 D2
0.50 0.67 0.83 1.00
VHS
Use inload combinations
6, 8 and 90.7 E
56 2
20 116 155 192 232
40 131 176 218 262
60 147 196 243 293
76 2
20 145 194 240 289
40 160 214 266 320
60 175 235 291 351
100 2
20 179 240 297 358
40 195 261 323 389
60 210 281 348 420
125 2
20 215 288 357 430
40 231 309 383 461
60 246 330 408 492
Table A1.4 Seismic VHS (lb/conn ASD)1, 6
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For SI: 1 in. = 25.4 mm; 1 ft. = 0.3048 m; 1 psf = 0.479 kN/m2; I lb. = 4.448 N1 Tabulated loads are based on a wall floor-to-ceiling clear height of 10 feet (3.0 m) for the first and second
stories. Loads are permitted to be reduced by multiplying by 0.95 where the average wall floor-to-ceilingclear height of the first and second stories does not exceed 9 feet (2.7 m).
2 Tabulated weight includes concrete weight only. 13 psf (0.62 kN/m2) additional weight is permitted forcombined interior and exterior wall finishes. See Table 2.1 for weights of walls within the scope of thisStandard.
3 Interpolation between tabulated SDS values is permitted. For Seismic Design Category C, interpolationbetween 0.50 and the lower-bound threshold SDS value of 0.33 is permitted.
4 Tabulated loads are based on a connection spacing of 12 inches (305 mm). For other spacings, multiple valuefrom table by desired connection spacing in inches (mm) and divide by 12 (305).
LoadingMaximumconcrete
wall weight (psf)2
Seismic design category and maximum SDS value (g )3
C D0 D1 D2
0.50 0.67 0.83 1.00
TSUse in loadcombinations7, 8 and 9
0.7 E
56 213 285 353 425
76 274 367 455 548
100 348 466 578 696
125 425 570 706 850
Table A1.5 Seismic TS (lb/conn ASD)1, 4
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Appendix A
A.3 DETAIL 2 ASD LOAD TABLESFigure A.2 Detail 2 is for the connection of a light-framedsecond story to a first story concrete wall similar to theconnection details of Figures 6.7 through 6.10. Three loadsact on this connection simultaneously (Figure A.2). Oneconnection device shall be capable of resisting all threeloads, or alternately two or more connection devices shall bepermitted. Although Figure A.2 depicts cold-formed steelframing members, the load combinations and tables in thissection also apply to wood framing members.
DETAIL 2 ASD LOAD COMBINATIONSFor all buildings, connector devices shall be capable ofresisting not less than the following ASD load combinations:
1. TV1 (within distance 2a of building corner)
2. TV2 (more than distance 2a from building corner)
3. VHW
4. VOW4
5. TV5 + VOW5 + VHW (within distance 2a of building corner)
6. TV6 + VOW5 + VHW (more than distance 2a from buildingcorner)
VOW or VOS(OUT-OF-PLANE)
TV
VHW or VHS(IN-PLANE)
Figure A.2. Detail 2 Loads
Where TV1, TV2, TV5, TV6, VHW, VOW4, VOW5 and VOW6 aredetermined from Tables A2.1 through A2.4. VHW shall betaken as the larger of VHW1 from Table A2.2 and VHW2 fromTable A2.3. In no case shall VOW be taken as less than 200pounds per linear foot (2.92 kN/m) times the anchor spacing.Where TV is negative in Table A2.1, a value of zero (0) ispermitted to be used. Distance “a” is determined from TableA2.1, Note 4.
For multiple dwellings assigned to Seismic Design CategoryC, and all buildings assigned to Seismic Design Category D0,D1 or D2, connector devices shall also be capable of resistingthe following additional ASD load combinations:
7. VHS
8. VOS
9. VHS + VOS
Where VHS and VOS are determined from Tables A2.5 andA2.6. In no case shall VOS be taken as less than 200 poundsper linear foot (2.92 kN/m) times the anchor spacing.
Selected connectors shall be capable of resisting the aboveloads acting alone or in combination.
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For SI: 1 in. = 25.4 mm; 1 ft. = 0.3048 m; 1 mph = 0.4470 m/s; 1 psf = 0.0479 kN/m2; I lb. = 4.448 N1 A positive tabulated value indicates an uplift load, a negative value is acting downward and is permitted to be taken as zero for connection design.Negative values are provided for interpolation purposes.
2 For intermediate roof slopes use the larger tabulated value, or determine the value by interpolation.3 For intermediate roof spans use the next larger tabulated span, or determine the value by interpolation.4 Distance “a” is 10% of the least horizontal dimension of the building or 0.4 times the mean roof height, whichever is smaller, but not less than 3feet (914 mm).
5 Tabulated loads are based on a connection spacing of 12 inches (305 mm). For other spacings, multiple value from table by desiredconnection spacing in inches (mm) and divide by 12 (305).
Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
A-8
LoadingRoofslope(angle)2
Roofspan(ft)3
aDimension
(ft)4
Exposure category, basic wind speed (mph) and velocity pressure (psf)
85B 90B 100B 110B 120B 130B 140B 150B 166B 179B 192B85C 90C 100C 110C 120C 130C 140C 150C 163C
85D 90D 100D 110D 120D 130D 140D 150D11.51 12.90 15.95 19.28 22.94 26.92 31.79 37.41 43.90 50.91 58.45
TV1, TV5Use in load
combinations 1 and 51.0W+0.6Dend condition(within 2a of
building corner)
0:12 to 1:12(0-5 degrees)
20 3 35 51 84 120 160 203 257 318 389 465 54730 3 53 76 126 180 240 305 385 477 583 697 82140 4 71 101 168 240 320 407 513 636 777 930 1094
4.4:12(20 degrees)
20 3 41 57 92 130 172 218 273 337 412 492 57830 3 61 85 137 194 256 324 407 503 613 733 86140 4 80 111 180 256 338 428 538 665 812 970 1141
7:12(30 degrees)
20 3 -39 -33 -20 -5 11 29 50 75 104 135 16830 3 -62 -53 -33 -12 11 37 68 104 145 190 23840 4 -86 -74 -49 -22 8 41 81 127 180 237 299
12:12(45 degrees)
20 3 -46 -41 -30 -17 -3 12 30 52 76 103 13130 3 -78 -71 -56 -39 -21 -1 23 51 84 118 15640 4 -114 -106 -89 -70 -49 -27 1 33 70 110 153
Add for each foot of roofoverhang span 15 18 23 29 35 42 51 61 72 84 97
All roof slopes20 38 54 88 125 165 210 264 326 399 477 56130 46 67 115 167 225 287 364 452 554 664 78240 52 80 141 208 282 362 460 573 704 845 997
Table A2.1Wind TV (lb/conn ASD)1, 5
8 9 12 16 20 24 29 35 42 50 58
TV2, TV6 Use inload combinations2 and 6 1.0W+0.6Dinterior condition(at least 2a frombuilding corner)
Add for each foot ofroof overhang span
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A-9
Appendix A
For SI: 1 in. = 25.4 mm; 1 ft. = 0.3048 m; 1 mph = 0.4470 m/s; 1 psf = 0.0479 kN/m2; I lb. = 4.448 N1 Tabulated loads are based on a wall floor-to-ceiling clear height of 10 feet (3.0 m) for the first and second stories. Loads are permitted to be reducedby multiplying by 0.91 where the average wall floor-to-ceiling clear height of the first and second stories does not exceed 9 feet (2.7 m).
2 For intermediate roof slopes use the larger tabulated value, or determine the value by interpolation.3 For intermediate values of building sidewall length, L, use the value for the next larger tabulated building dimension, or determine by interpolation.4 Tabulated loads are based on a diaphragm aspect ratio, L / W of 2. Tabulated values are permitted to be reduced by multiplying by 0.50 for adiaphragm aspect ratio, L / W, of 1, and by 0.25 for a diaphragm aspect ratio of 0.5. Interpolation for other values of aspect ratios, L / W, between 2and 0.5 is permitted.
5 Reduction of tabulated loads based on diaphragm aspect ratio is not permitted.6 Tabulated loads are based on a connection spacing of 12 inches (305 mm). For other spacings, multiple value from table by desired connectionspacing in inches (mm) and divide by 12 (305).
LoadingRoofslope(angle)2
Sidewalllength, L
(parallel to ridge)(ft)3
Exposure category, basic wind speed (mph) and velocity pressure (psf)85B 90B 100B 110B 120B 130B 140B 150B 166B 179B 192B
85C 90C 100C 110C 120C 130C 140C 150C 163C85D 90D 100D 110D 120D 130D 140D 150D
11.51 12.90 15.95 19.28 22.94 26.92 31.79 37.41 43.90 50.91 58.45
VHW1Use larger of VHW1and VHW2 in loadcombinations 3, 5
and 6W
0:12 to 1:12(0-5 degrees)4
20 225 252 312 377 449 527 622 732 859 996 114440 234 262 324 392 466 547 646 760 892 1034 118760 234 262 324 392 466 547 646 760 892 1034 1187
4.4:12(20 degrees)4
20 274 307 379 459 546 640 756 890 1044 1211 139140 277 310 383 463 551 647 764 899 1055 1223 140460 277 310 383 463 551 647 764 899 1055 1223 1404
7:12(30 degrees)5
20 274 308 380 460 547 642 758 892 1046 1214 139340 316 354 437 529 629 738 872 1026 1204 1396 160360 347 389 481 581 691 811 958 1128 1323 1534 1762
12:12(45 degrees)5
20 297 332 411 497 591 694 819 964 1131 1312 150640 362 405 501 606 721 846 999 1175 1379 1599 183660 416 466 576 697 829 973 1148 1352 1586 1839 2112
Table A2.2 Wind VHWI Wind Perpendicular to Ridge (lb/conn ASD)1, 6
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For SI: 1 in. = 25.4 mm; 1 ft. = 0.3048 m; 1 mph = 0.4470 m/s; 1 psf = 0.0479 kN/m2; I lb. = 4.448 N1 Tabulated loads are based on a wall floor-to-ceiling clear height of 10 feet (3.0 m) for the first and second stories. Loads are permitted to be reducedby multiplying by 0.91 where the average wall floor-to-ceiling clear height of the first and second stories does not exceed 9 feet (2.7 m).
2 For intermediate roof slopes use the larger tabulated value, or determine the value by interpolation.3 For intermediate values of building endwall length, W, use tabulated plan dimension that results in larger VHW2, or determine by interpolation.4 Tabulated loads are based on a diaphragm aspect ratio, W/ L, of 2. Tabulated values are permitted to be reduced by multiplying by 0.50 for adiaphragm aspect ratio, W/ L, of 1, and by 0.25 for a diaphragm aspect ratio of 0.5. Interpolation for other values of aspect ratios, W/ L, between 2and 0.5 is permitted.
5 Tabulated loads are based on a connection spacing of 12 inches (305 mm). For other spacings, multiple value from table by desired connectionspacing in inches (mm) and divide by 12 (305).
LoadingRoofslope(angle)2
Endwalllength, W
(perpendicularto ridge)(ft)3,4
Exposure category, basic wind speed (mph) and velocity pressure (psf)
85B 90B 100B 110B 120B 130B 140B 150B 166B 179B 192B
85C 90C 100C 110C 120C 130C 140C 150C 163C
85D 90D 100D 110D 120D 130D 140D 150D
11.51 12.90 15.95 19.28 22.94 26.92 31.79 37.41 43.90 50.91 58.45
VHW2Use largerof VHW1 andVHW2 in loadcombinations3, 5 and 6
W
0:12 to 1:12(0-5 degrees)
20 163 183 226 273 325 382 451 531 623 722 829
40 156 175 216 262 311 365 431 508 596 691 793
60 159 178 221 267 317 372 440 517 607 704 808
4.4:12(20 degrees)
20 174 195 241 291 346 406 480 565 662 768 882
40 175 196 243 293 349 409 483 569 668 774 889
60 187 210 260 314 374 438 518 609 715 829 952
7:12(30 degrees)
20 182 204 252 304 362 425 502 591 693 804 923
40 192 215 266 321 382 448 530 623 731 848 974
60 214 240 296 358 426 500 591 695 816 946 1086
12:12(45 degrees)
20 198 222 274 331 394 462 546 643 754 875 1004
40 221 247 306 370 440 516 610 717 842 976 1121
60 258 289 357 432 513 603 712 837 983 1140 1308
Table A2.3 Wind VHW2 Wind Parallel to Ridge (lb/conn ASD)1, 5
LoadingRoofslope(angle)2
Exposure category, basic wind speed (mph) and velocity pressure (psf)
85B 90B 100B 110B 120B 130B 140B 150B 166B 179B 192B
85C 90C 100C 110C 120C 130C 140C 150C 163C
85D 90D 100D 110D 120D 130D 140D 150D
11.51 12.90 15.95 19.28 22.94 26.92 31.79 37.41 43.90 50.91 58.45
VOW4Use in load combination 4
Wcomponents & cladding
All roof slopes3 74 83 102 123 147 172 203 239 281 326 374
VOW5, VOW6Use in loadcombinations
5 and 6W
MWFRS
0:12 to 1:12(0-5 degrees) 27 30 37 45 54 63 75 88 103 120 137
4.4:12(20 degrees) 35 39 49 59 70 82 97 114 134 155 178
7:12 to 12:12(30-45 degrees) 32 35 44 53 63 74 87 103 121 140 161
Table A2.4 Wind VOW (lb/conn ASD)1, 4
For SI: 1 in. = 25.4 mm; 1 mph = 0.4470 m/s; 1 psf = 0.0479 kN/m2; I lb. = 4.448 N1 Tabulated loads are based on a wall floor-to-ceiling clear height of 10 feet (3.0 m) for the first and second stories. Loads are permitted to be reducedby multiplying by 0.90 where the average wall floor-to-ceiling clear height of the first and second stories does not exceed 9 feet (2.7 m).
2 Linear interpolation between tabulated roof slopes is permitted.3 Tabulated components and cladding loads are permitted to be reduced by multiplying by 0.91 for roof slopes less than or equal to 2.12:12 (10degrees).
4 Tabulated loads are based on a connection spacing of 12 inches (305 mm). For other spacings, multiple value from table by desired connectionspacing in inches (mm) and divide by 12 (305).
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A-11
Appendix A
Loading
Maximumconcrete wall
weight(psf)2
Ratio of largerbuilding plandimension to
smaller buildingplan dimension3
Largerbuildingplan
dimension(ft)4
Seismic design category andmaximum SDS value (g )5
C D0 D1 D2
0.50 0.67 0.83 1.00
VHSUse in loadcombinations
7 and 90.7 E
56 2
20 118 159 197 237
40 160 214 266 320
60 202 270 335 403
76 2
20 133 178 220 266
40 174 234 289 349
60 216 289 358 432
100 2
20 147 197 244 294
40 189 253 313 378
60 230 309 382 461
125 2
20 164 219 271 327
40 205 275 341 410
60 247 331 410 493
Table A2.5 Seismic VHS (lb/conn ASD)1, 6
For SI: 1 in. = 25.4 mm; 1 ft. = 0.3048 m; 1 psf = 0.0479 kN/m2; I lb. = 4.448 N1 Tabulated loads are based on a wall floor-to-ceiling clear height of 10 feet (3.0 m) for the first and second stories. Loads are permitted to be reducedby multiplying by 0.91 where the average wall floor-to-ceiling clear height of the first and second stories does not exceed 9 feet (2.7 m).
2 Tabulated weight includes concrete weight only. 13 psf (0.62 kN/m2) additional weight is permitted for combined interior and exterior wall finishes.See Table 2.1 for weights of walls within the scope of this Standard.
3 Tabulated loads are based on a diaphragm aspect ratio of 2 (ratio of larger plan dimension to smaller plan dimension). Tabulated values are permittedto be reduced by multiplying by 0.60 for a diaphragm aspect ratio of 1. Interpolation between aspect ratios of 2 and 1 is permitted.
4 For intermediate larger building plan dimensions, use the value for the next larger tabulated building dimension, or determine by interpolation.5 Interpolation between tabulated SDS values is permitted. For Seismic Design Category C, interpolation between 0.50 and the lower-bound threshold
SDS value of 0.33 is permitted.6 Tabulated loads are based on a connection spacing of 12 inches (305 mm). For other spacings, multiple value from table by desired connectionspacing in inches (mm) and divide by 12 (305).
Loading
Maximumconcrete
wall weight(psf)2
Seismic design category and maximum SDS value (g )3
C D0 D1 D2
0.50 0.67 0.83 1.00
VOSUse in loadcombinatinos
8 and 90.7 E
56 97 129 160 193
76 125 167 207 249
100 158 212 263 316
125 193 259 321 386
Table A2.6 Seismic VOS (lb/conn ASD)1, 4
For SI: 1 in. = 25.4 mm; 1 psf = 0.0479 kN/m2; I lb. = 4.448 N1 Tabulated loads are based on a wall floor-to-ceiling clear height of 10 feet (3.0 m) for the first and second stories. Loads are permitted to be reducedby multiplying by 0.95 where the average wall floor-to-ceiling clear height of the first and second stories does not exceed 9 feet (2.7 m).
2 Tabulated weight includes concrete weight only. 13 psf (0.62 kN/m2) additional weight is permitted for combined interior and exterior wall finishes.See Table 2.1 for weights of walls within the scope of this Standard.
3 Interpolation between tabulated SDS values is permitted. For Seismic Design Category C, interpolation between 0.50 and the lower-bound thresholdSDS value of 0.33 is permitted.
4 Tabulated loads are based on a connection spacing of 12 inches (305 mm). For other spacings, multiple value from table by desired connectionspacing in inches (mm) and divide by 12 (305).
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A-12
A.4 DETAIL 3 ASD LOAD TABLESFigure A.3 Detail 3 is for the connection of a light-framedceiling and roof to the top of a concrete wall similar to theconnection details of Figures 6.11 through 6.14. Three loadsact on this connection simultaneously (Figure A.3). Oneconnection device shall be capable of resisting all threeloads, or alternately two or more connection devices shall bepermitted.
DETAIL 3 ASD LOAD COMBINATIONSFor all buildings, connector devices shall be capable ofresisting not less than the following ASD load combinations:
1. TV1 (within distance 2a of building corner)
2. TV2 (more than distance 2a from building corner)
3. VHW
4. VOW4
5. TV5 + VOW5 + VHW (within distance 2a of building corner)
6. VV6 + VOW6 + VHW (more than distance 2a from buildingcorner)
Figure A.3. Detail 3 loads.
Where TV1, TV2, TV5, TV6, VHW, VOW4, VOW5 and VOW6 aredetermined from Tables A3.1 through A3.4. VHW shall betaken as the larger of VHW1 from Table A3.2 and VHW2 fromTable A3.3. In no case shall VOW be taken as less than200 pounds per linear foot (2.92 kN/m) times the anchorspacing. Where TV is negative in Table A3.1, a value of zero(0) is permitted to be used. Distance “a” is determined fromTable A3.1, Note 4.
For multiple dwellings assigned to Seismic Design CategoryC, and all buildings assigned to Seismic Design Category D0,D1 or D2, connector devices shall also be capable of resistingthe following additional ASD load combinations:
7. VHS
8. VOS
9. VHS + VOS
Where VHS and VOS are determined from Tables A3.5 andA3.6. In no case shall VOS be taken as less than 200 poundsper linear foot (2.92 kN/m) times the anchor spacing.
Selected connectors shall be capable of resisting the aboveloads acting alone or in combination.
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A-13
Appendix A
LoadingRoofslope(angle)2
Roofspan(ft)3
aDimension
(ft)4
Exposure category, basic wind speed (mph), and velocity pressure (psf)
85B 90B 100B 110B 120B 130B 140B 150B 166B 179B 192B
85C 90C 100C 110C 120C 130C 140C 150C 163C
85D 90D 100D 110D 120D 130D 140D 150D
11.51 12.90 15.95 19.28 22.94 26.92 31.79 37.41 43.90 50.91 58.45
TV1, TV5Use in loadcombinations
1 and 51.0W+0.6D
endcondition
(within 2a ofbuilding corner)
0:12 to1:12(0–5
degrees)
20 3 35 51 84 120 160 203 257 318 389 465 547
30 3 53 76 126 180 240 305 385 477 583 697 821
40 4 71 101 168 240 320 407 513 636 777 930 1094
4.4:12(20
degrees)
20 3 41 57 92 130 172 218 273 337 412 492 578
30 3 61 85 137 194 256 324 407 503 613 733 861
40 4 80 111 180 256 338 428 538 665 812 970 1141
7:12(30
degrees)
20 3 -39 -33 -20 -5 11 29 50 75 104 135 168
30 3 -62 -53 -33 -12 11 37 68 104 145 190 238
40 4 -86 -74 -49 -22 8 41 81 127 180 237 299
12:12(45
degrees)
20 3 -46 -41 -30 -17 -3 12 30 52 76 103 131
30 3 -78 -71 -56 -39 -21 -1 23 51 84 118 156
40 4 -114 -106 -89 -70 -49 -27 1 33 70 110 153
Add for each foot of roofoverhand span 15 18 23 29 35 42 51 61 72 84 97
TV2, TV6Use in loadcombinations
2 and 61.0W+0.6D
interior condition(at least 2a frombuilding corner)
Allroofslopes
20 38 54 88 125 165 210 264 326 399 477 561
30 46 67 115 167 225 287 364 452 554 664 782
40 52 80 141 208 282 362 460 573 704 845 997
Add for each foot of roofoverhang span 8 9 12 16 20 24 29 35 42 50 58
Table A3.1 Wind TV (lb/conn ASD)1, 5
For SI: 1 in. = 25.4 mm; 1 ft. = 0.3048 m; 1 mph = 0.4470 m/s; 1 psf = 0.0479 kN/m2; I lb. = 4.448 N1 A positive tabulated value indicates an uplift load, a negative value is acting downward and is permitted to be taken as zero for connection design.Negative values are provided for interpolation purposes.
2 For intermediate roof slopes use the larger tabulated value, or determine the value by interpolation.3 For intermediate roof spans use the next larger tabulated span, or determine the value by interpolation.4 Distance “a” is 10% of the least horizontal dimension of the building or 0.4 times the mean roof height, whichever is smaller, but not less than 3 feet(914 mm).
5 Tabulated loads are based on a connection spacing of 12 inches (305 mm). For other spacings, multiple value from table by desired connectionspacing in inches (mm) and divide by 12 (305).
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Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
A-14
LoadingRoofslope(angle)2
Sidewalllength, L(parallel toridge) (ft)3
Exposure category, basic wind speed (mph), and velocity pressure (psf)85B 90B 100B 110B 120B 130B 140B 150B 166B 179B 192B
85C 90C 100C 110C 120C 130C 140C 150C 163C85D 90D 100D 110D 120D 130D 140D 150D
11.51 12.90 15.95 19.28 22.94 26.92 31.79 37.41 43.90 50.91 58.45
VHW1Use larger of
VHW1 and VHW2in load
combinations3, 5 and 6
W
0:12 to 1:12(0-5 degrees)4
20 50 56 69 84 100 117 138 162 191 221 254
40 47 53 65 79 94 110 130 153 179 208 238
60 47 53 65 79 94 110 130 153 179 208 238
4.4:12(20 degrees)4
20 69 78 96 116 138 162 192 225 264 307 352
40 65 73 90 109 130 152 180 212 249 288 331
60 65 73 90 109 130 152 180 212 249 288 331
7:12(30 degrees)5
20 85 96 118 143 170 200 236 277 326 378 434
40 106 119 147 178 211 248 293 345 404 469 538
60 130 145 180 217 259 304 358 422 495 574 659
12:12(45 degrees)5
20 121 136 168 203 241 283 335 394 462 536 615
40 175 197 243 294 350 410 485 570 669 776 891
60 234 262 324 392 466 547 646 760 892 1035 1188
For SI: 1 in. = 25.4 mm; 1 ft. = 0.3048 m; 1 mph = 0.4470 m/s; 1 psf = 0.0479 kN/m2; I lb. = 4.448 N1 Tabulated loads are based on a top story wall floor-to-ceiling clear height of 10 feet (3.0 m). Loads are permitted to be reduced by multiplying by 0.90where the top story wall floor-to-ceiling clear height does not exceed 8 feet (2.4 m), or by 0.95 where the top story wall floor-to-ceiling clear heightdoes not exceed 9 feet (2.7 m).
2 For intermediate roof slopes use the larger tabulated value, or determine the value by interpolation.3 For intermediate values of building sidewall length, L, use the value for the larger tabulated value, or determine by interpolation.4 Tabulated loads are based on a diaphragm aspect ratio, L / W of 2. Tabulated values are permitted to be reduced by multiplying by 0.50 for adiaphragm aspect ratio, L / W, of 1, and by 0.25 for a diaphragm aspect ratio of 0.5. Interpolation for other values of aspect ratios, L / W, between 2and 0.5 is permitted.
5 Reduction of tabulated loads based on diaphragm aspect ratio is not permitted.6 Tabulated loads are based on a connection spacing of 12 inches (305 mm). For other spacings, multiple value from table by desired connectionspacing in inches (mm) and divide by 12 (305).
Table A3.2 Wind VHW1 Wind Perpendicular to Ridge (lb/conn ASD)1, 6
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A-15
Appendix A
LoadingRoofslope(angle)2
Endwalllength,
W,(perpendicularto ridge) (ft)3,4
Exposure category, basic wind speed (mph), and velocity pressure (psf)
85B 90B 100B 110B 120B 130B 140B 150B 166B 179B 192B85C 90C 100C 110C 120C 130C 140C 150C 163C
85D 90D 100D 110D 120D 130D 140D 150D11.51 12.90 15.95 19.28 22.94 26.92 31.79 37.41 43.90 50.91 58.45
VHW2Use larger of
VHW1 and VHW2in load
combinations3, 5 and 6
W
0:12 to 1:12(0-5 degrees)
20 53 60 74 89 106 125 147 173 203 236 27140 53 59 73 89 105 124 146 172 202 234 26960 56 63 77 94 111 131 154 182 213 247 284
4.4:12(20 degrees)
20 64 71 88 107 127 149 176 207 243 282 32440 72 80 99 120 143 168 198 233 274 317 36460 84 94 117 141 168 197 232 273 321 372 427
7:12(30 degrees)
20 72 80 99 120 143 168 198 233 274 317 36440 87 98 121 146 174 204 241 283 332 385 44260 108 121 150 181 215 252 298 351 412 477 548
12:12(45 degrees)
20 88 98 122 147 175 205 242 285 335 388 44640 116 130 161 194 231 272 321 377 443 514 59060 152 170 210 254 302 355 419 493 579 671 770
Table A3.3 Wind VHW2 Wind Parallel to Ridge (lb/conn ASD)1, 5
For SI: 1 in. = 25.4 mm; 1 ft. = 0.3048 m; 1 mph = 0.4470 m/s; 1 psf = 0.0479 kN/m2; I lb. = 4.448 N1 Tabulated loads are based on a top story wall floor-to-ceiling clear height of 10 feet (3.0 m). Loads are permitted to be reduced by multiplying by 0.90where the top story wall floor-to-ceiling clear height does not exceed 8 feet (2.4 m), or by 0.95 where the top story wall floor-to-ceiling clear heightdoes not exceed 9 feet (2.7 m).
2 For intermediate roof slopes use the larger tabulated value, or determine the value by interpolation.3 For intermediate values of building endwall length, W, use tabulated plan dimension that results in larger VHW2, or determine by interpolation.4 Tabulated loads are based on a diaphragm aspect ratio, W/L, of 2. Tabulated values are permitted to be reduced by multiplying by 0.50 for adiaphragm aspect ratio, W/L, of 1, and by 0.25 for a diaphragm aspect ratio of 0.5. Interpolation for other values of aspect ratios, W/L, between 2and 0.5 is permitted.
5 Tabulated loads are based on a connection spacing of 12 inches (305 mm). For other spacings, multiple value from table by desired connectionspacing in inches (mm) and divide by 12 (305).
LoadingRoofslope(angle)2
Exposure category, basic wind speed (mph), and velocity pressure (psf)
85B 90B 100B 110B 120B 130B 140B 150B 166B 179B 192B
85C 90C 100C 110C 120C 130C 140C 150C 166C
85D 90D 100D 110D 120D 130D 140D 150D
11.51 12.90 15.95 19.28 22.94 26.92 31.79 37.41 43.90 50.91 58.45
VOW4 Use in loadcombination 4
Wcomponents & cladding
All roofslopes3 74 83 102 123 147 172 203 239 281 326 374
VOW5, VOW6Use in loadcombinations
5 and 6W
MWFRS
0:12 to 1:12(0-5 degrees) 27 30 37 45 54 63 75 88 103 120 137
4.4:12(20 degrees) 35 39 49 59 70 82 97 114 134 155 178
7:12 to 12:12(30-45 degrees) 32 35 44 53 63 74 87 103 121 140 161
Table A3.4 Wind VOW (lb/conn ASD)1, 4
For SI: 1 in. = 25.4 mm; 1 mph = 0.4470 m/s; 1 psf = 0.0479 kN/m2; I lb. = 4.448 N1 Tabulated loads are based on a top story wall floor-to-ceiling clear height of 10 feet (3.0 m). Loads are permitted to be reduced by multiplying by 0.80where the top story wall floor-to-ceiling clear height does not exceed 8 feet (2.4 m), or by 0.90 where the top story wall floor-to-ceiling clear heightdoes not exceed 9 feet (2.7 m).
2 For intermediate roof slopes use the larger tabulated value, or determine the value by interpolation.3 Tabulated components and cladding loads are permitted to be multiplied by 0.91 for roof slopes less than or equal to 2.12:12 (10 degrees).4 Tabulated loads are based on a connection spacing of 12 inches (305 mm). For other spacings, multiple value from table by desired connectionspacing in inches (mm) and divide by 12 (305).
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Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
A-16
For SI: 1 in. = 25.4 mm; 1 ft. = 0.3048 m; 1 psf = 0.0479 kN/m2; I lb. = 4.448 N1 Tabulated loads are based on a top story wall floor-to-ceiling clear height of 10 feet (3.0 m). Loads are permitted to be reduced by multiplying by 0.90where the top story wall floor-to-ceiling clear height does not exceed 8 feet (2.4 m), or by 0.95 where the top story wall floor-to-ceiling clear heightdoes not exceed 9 feet (2.7 m).
2 Tabulated weight includes concrete weight only. 13 psf (0.62 kN/m2) additional weight is permitted for combined interior and exterior wall finishes.See Table 2.1 for weights of walls within the scope of this Standard.
3 Tabulated loads are based on a diaphragm aspect ratio of 2 (ratio of larger plan dimension to smaller plan dimension). Tabulated values are permittedto be reduced by multiplying by 0.60 for a diaphragm aspect ratio of 1. Interpolation between aspect ratios of 2 and 1 is permitted.
4 For intermediate larger building plan dimensions use the value for the larger tabulated building dimension, or determine by interpolation.5 Interpolation between tabulated SDS values is permitted. For Seismic Design Category C, interpolation between 0.50 and the lower-bound threshold
SDS value of 0.33 is permitted.6 Tabulated loads are based on a connection spacing of 12 inches (305 mm). For other spacings, multiple value from table by desired connectionspacing in inches (mm) and divide by 12 (305).
Table A3.5 Seismic VHS (lb/conn ASD)1, 6
Loading
Maximumconcrete
wall weight(psf)2
Ratio of larger buildingplan dimension to
smaller building plandimension (ft)3
Larger buildingplan dimension
(ft)4
Seismic design category andmaximum SDS value (g )5
C D0 D1 D20.50 0.67 0.83 1.00
VHSUse in loadcombinations
7 and 90.7 E
56 2
20 63 85 105 127
40 79 106 131 158
60 94 126 157 189
76 2
20 77 103 127 153
40 92 123 153 184
60 107 144 178 215
100 2
20 104 139 172 208
40 119 160 198 238
60 135 180 223 269
125 2
20 109 146 180 217
40 124 166 206 248
60 139 187 231 279
Maximum concretewall weight (psf)2
Seismic Design Category and Maximum SDS Value (g )3
C D0 D1 D20.50 0.67 0.83 1.00
VOSUse in loadcombinations
8 and 90.7 E
56 97 129 160 193
76 125 167 207 249
100 158 212 263 316
125 193 259 321 386
Table A3.6 Seismic VOS (lb/conn ASD)1, 4
For SI: 1 in. = 25.4 mm; 1 psf = 0.0479 kN/m2; I lb. = 4.448 N1 Tabulated loads are based on a top story wall floor-to-ceiling clear height of 10 feet (3.0 m). Loads are permitted to be reduced by multiplying by 0.80where the top story wall floor-to-ceiling clear height does not exceed 8 feet (2.4 m), or by 0.90 where the top story wall floor-to-ceiling clear heightdoes not exceed 9 feet (2.7 m).
2 Tabulated weight includes concrete weight only. 13 psf (0.62 kN/m2) additional weight is permitted for combined interior and exterior wall finishes.See Table 2.1 for weights of walls within the scope of this Standard.
3 Interpolation between tabulated SDS values is permitted. For Seismic Design Category C, interpolation between 0.50 and the lower-bound thresholdSDS value of 0.33 is permitted.
4 Tabulated loads are based on a connection spacing of 12 inches (305 mm). For other spacings, multiple value from table by desired connectionspacing in inches (mm) and divide by 12 (305).
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B-1
Appendix BLRFD Load Tables and Load Combinations forConcrete Wall Connections toLight-Framed Floor, Ceiling and Roof Systems
B.1 GENERALAppendix B load tables are provided to allow the design ofconnections or selection of proprietary connector devices,as an alternative to connection details Figures 6.3 through6.14. Connector devices shall be installed in accordance withthe manufacturer’s installation instructions and applicablerequirements from evaluation reports.
For each connection detail, Load and Resistance FactorDesign (LRFD) (strength design) load tables and load combi-nations are provided in this appendix. Allowable stressdesign (ASD) load tables and load combinations are providedin Appendix A. The use of either ASD or LRFD loads and loadcombinations is permitted, however mixing of ASD and LRFDis not permitted.
In order to use the Appendix B tables, the following informa-tion must be identified:
1. Whether one or multiple connectors will be used
2. Connector spacing(s) (in)
3. The floor joist span perpendicular to the wall (ft)
4. Roof angle (degrees or rise to run)
5. Larger building plan dimension (ft)
6. Ratio of larger to smaller building plan dimension (roofand floor aspect ratio)
7. Basic wind speed (mph) and exposure category (B, Cor D)
8. Seismic Design Category (SDC)
B.2 DETAIL 1 LRFD LOAD TABLESFigure B.1 Detail 1 is for the connection of a two-storyconcrete wall to a light-framed floor system (floor diaphragm)similar to the connection details of Figures 6.3 through 6.6.Three loads act on this connection simultaneously (Figure
B.1). One connection device shall be capable of resisting allthree loads, or alternately two or more connection devicesshall be permitted. Although Figure B.1 depicts cold-formedsteel framing members, the load combinations and tables inthis section also apply to wood framing members.
DETAIL 1 LRFD LOAD COMBINATIONSFor all buildings, connector devices shall be capable ofresisting not less than the following LRFD load combinations:
1. VV1
2. VHW
3. TW3
4. VV4 + VHW + TW4
Where VV1, VV4, VHW, TW3 and TW4 are determined fromTables B1.1 through B1.3. In no case shall TW3 or TW4 betaken as less than 280 pounds per linear foot (4.09 kN/m)times the anchor spacing.
For multiple dwellings assigned to Seismic Design CategoryC, and all buildings assigned to Seismic Design Category D0,
TW or TS
VV
VHW or VHS(IN-PLANE)
Figure B.1. Detail 1 loads.
Appendix B is adopted by reference within Chapter 6 of the Standard;therefore, it is a mandatory part of the Standard.
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Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
B-2
D1 or D2, connector devices shall also be capable of resistingthe following additional LRFD load combinations:
5. VHS
6. TS
7. VV7 + VHS + TS
Where VV7, VHS and TS are determined from Tables B1.1,B1.4 and B1.5. In no case shall TS be taken as less than 280pounds per linear foot (4.09 kN/m) times the anchor spacing.
Selected connectors shall be capable of resisting the aboveloads acting alone or in combination.
LoadingFloor joist span perpendicular to wall (ft)1, 2
12 16 20 24 28 32
VV1Use in load combination 1
1.2D+1.6L456 608 760 912 1064 1216
VV4Use in load combination 4
1.2D+0.5L192 256 320 384 448 512
VV7Use in load combination 7
1.4D+0.5L204 272 340 408 476 544
Table B1.1 VV (lb/conn LRFD)3
For SI: I in. = 25.4 mm; 1 ft. = 0.3048 m; I lb. = 4.448 N1 Interpolation between tabulated floor joist spans is permitted.2 For joists spanning parallel to the concrete wall, VV is permitted to be taken as zero.3 Tabulated loads are based on a connection spacing of 12 inches (305 mm). For other spacings, multiple value from table by desired connection
spacing in inches (mm) and divide by 12 (305).
LoadingRoofslope
(angle)3
Largerbuilding
plandimension
(ft)4
Exposure category, basic wind speed (mph) and velocity pressure (psf)
85B 90B 100B 110B 120B 130B 140B 150B 166B 179B 192B
85C 90C 100C 110C 120C 130C 140C 150C 163C
85D 90D 100D 110D 120D 130D 140D 150D
11.51 12.9 15.95 19.28 22.94 26.92 31.79 37.41 43.9 50.91 58.45
VHWUse in loadcombintions
2 and 41.6W
0:12 to1:12(0–5
degrees)
20 176 197 244 295 351 411 486 572 671 778 893
40 159 179 221 267 318 373 440 518 608 705 810
60 153 172 212 257 305 358 423 498 585 678 778
4.4:12(20
degrees)
20 244 274 338 409 486 571 674 793 931 1080 1239
40 221 248 307 371 441 518 612 720 845 980 1125
60 213 239 295 357 424 498 588 692 812 942 1081
7:12 to12:12(30–45degrees)
20 213 239 295 357 425 499 589 693 813 943 1083
40 202 226 280 338 402 472 558 656 770 893 1025
60 198 222 274 331 394 462 546 642 754 874 1004
Table B1.2 Wind VHW (lb/conn LRFD)1, 2, 5
For SI: 1 in. = 25.4 mm; 1 ft. = 0.3048 m; 1 mph = 0.4470 m/s; 1 psf = 0.0479 kN/m2; I lb. = 4.448 N1 Tabulated loads are based on a diaphragm aspect ratio of 2 (ratio of larger plan dimension to smaller plan dimension). Tabulated values are permitted
to be reduced by multiplying by 0.50 for a diaphragm aspect ratio of 2 to 1. Interpolation between aspect ratios of 2 and 1 is permitted.2 Tabulated loads are based on a wall floor-to-ceiling clear height of 10 feet (3.0 m) for the first and second stories. Loads are permitted to be reduced
by multiplying by 0.91 where the average wall floor-to-ceiling clear height of the first and second stories does not exceed 9 feet (2.7 m).3 For intermediate roof slopes use the larger tabulated value, or determine the value by interpolation.4 For intermediate larger building plan dimensions, use the value for the next smaller tabulated building dimension, or determine by interpolation.5 Tabulated loads are based on a connection spacing of 12 inches (305 mm). For other spacings, multiple value from table by desired connection
spacing in inches (mm) and divide by 12 (305).
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B-3
Appendix B
LoadingRoofslopes
(angle)2
Exposure category, basic wind speed (mph) and velocity pressure (psf)
85B 90B 100B 110B 120B 130B 140B 150B 166B 179B 192B
85C 90C 100C 110C 120C 130C 140C 150C 163C
85D 90D 100D 110D 120D 130D 140D 150D
11.51 12.9 15.95 19.28 22.94 26.92 31.79 37.41 43.9 50.91 58.45
TW3Use in load
combination 31.6W
components& cladding
Allroof
slopes(angles)2
259 291 359 434 517 606 716 843 989 1147 1317
TW4Use in load
combination 41.6W
MWFRS
0:12 to1:12(0–5
degrees)
95 107 132 159 190 223 263 309 363 421 483
4.4:12(20
degrees)124 138 171 207 246 289 341 402 471 547 628
7:12 to12:12(30–45degrees)
111 125 154 187 222 261 308 362 425 493 566
Table B1.3 Wind TW (lb/conn LRFD)1, 4
For SI: 1 in. = 25.4 mm; 1 mph = 0.4470 m/s; 1 psf = 0.0479 kN/m2; I lb. = 4.448 N1 Tabulated loads are based on a wall floor-to-ceiling clear height of 10 feet (3.0 m) for the first and second stories. Loads are permitted to be reduced
by multiplying by 0.91 where the average wall floor-to-ceiling clear height of the first and second stories does not exceed 9 feet (2.7 m).2 For intermediate roof slopes use the larger tabulated value, or determine the value by interpolation.3 Tabulated TW 3 loads are permitted to be reduced by multiplying by 0.91 for roof slopes less than or equal to 2.12:12 (10 degrees).4 Tabulated loads are based on a connection spacing of 12 inches (305 mm). For other spacings, multiple value from table by desired connection
spacing in inches (mm) and divide by 12 (305).
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Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
B-4
Table B1.4 Seismic VHS (lb/conn LRFD)1, 6
LoadingMaximum
concrete wallweight, (psf)2
Ratio of larger buildingplan dimension to smallerbuilding plan dimension3
Largerbuilding plan
dimension, (ft)4
Seismic design category and maximum SDS value ( g )5
C D0 D1 D2
0.50 0.67 0.83 1.00
VHSUse in load
combinations5 and 7
E
56 2
20 165 222 275 331
40 187 251 311 375
60 209 281 348 419
76 2
20 207 277 343 413
40 229 306 379 457
60 251 336 416 501
100 2
20 256 343 425 512
40 278 372 461 556
60 300 402 498 600
125 2
20 307 412 510 615
40 329 441 547 659
60 351 471 583 703
For SI: 1 in. = 25.4 mm; 1 ft. = 0.3048 m; 1 psf = 0.479 kN/m2; I lb. = 4.448 N1 Tabulated loads are based on a wall floor-to-ceiling clear height of 10 feet (3.0 m) for the first and second stories. Loads are permitted to be reduced
by multiplying by 0.95 where the average wall floor-to-ceiling clear height of the first and second stories does not exceed 9 feet (2.7 m).2 Tabulated weight includes concrete weight only. 13 psf (0.62 kN/m2) additional weight is permitted for combined interior and exterior wall finishes.
See Table 2.1 for weights of walls within the scope of this Standard.3 Tabulated loads are based on a diaphragm aspect ratio of 2 (ratio of larger plan dimension to smaller plan dimension). Tabulated values are permitted
to be reduced by multiplying by 0.60 for a diaphragm aspect ratio of 1. Interpolation between aspect ratios of 2 and 1 is permitted.4 For intermediate larger building plan dimensions, use the value for the next larger tabulated building dimension, or determine by interpolation.5 Interpolation between tabulated SDS values is permitted. For Seismic Design Category C, interpolation between 0.50 and the lower-bound threshold
SDS value of 0.33 is permitted.6 Tabulated loads are based on a connection spacing of 12 inches (305 mm). For other spacings, multiple value from table by desired connection
spacing in inches (mm) and divide by 12 (305).
Table B1.5 Seismic TS (lb/conn LRFD)1,4
LoadingMaximum concretewall weight (psf)2
Seismic Design Category and maximum SDS value ( g )3
C D0 D1 D2
0.50 0.67 0.83 1.00TS
Use in loadcombinations
6 and 7E
56 304 407 504 607
76 392 525 650 783
100 497 666 825 994
125 607 814 1008 1214
For SI: 1 in. = 25.4 mm; 1 psf = 0.0479 kN/m2; I lb. = 4.448 N1 Tabulated loads are based on a wall floor-to-ceiling clear height of 10 feet (3.0 m) for the first and second stories. Loadsare permitted to be reduced by multiplying by 0.95 where the average wall floor-to-ceiling clear height of the first andsecond stories does not exceed 9 feet (2.7 m).
2 Tabulated weight includes concrete weight only. 13 psf (0.62 kN/m2) additional weight is permitted for combined inte-rior and exterior wall finishes. See Table 2.1 for weights of walls within the scope of this Standard.
3 Interpolation between tabulated SDS values is permitted. For Seismic Design Category C, interpolation between 0.50and the lower-bound threshold SDS value of 0.33 is permitted.
4 Tabulated loads are based on a connection spacing of 12 inches (305 mm). For other spacings, multiple value from table bydesired connection spacing in inches (mm) and divide by 12 (305).
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B-5
Appendix B
B.3 DETAIL 2 LRFD LOAD TABLES
Figure B.2 Detail 2 is for the connection of a light-framedstory to a first story concrete wall similar to the connectiondetails of Figures 6.7 through 6.10. Three loads act on thisconnection simultaneously (Figure B.2). One connectiondevice shall be capable of resisting all three loads, oralternately two or more connection devices shall bepermitted. Although Figure B.2 depicts cold-formed steelframing members, the load combinations and tables in thissection also apply to wood framing members.
VOW or VOS(OUT-OF-PLANE)
TV
VHW or VHS(IN-PLANE)
Figure B.2 Detail 2 Loads.
DETAIL 2 LRFD LOAD COMBINATIONSFor all buildings, connector devices shall be capable ofresisting not less than the following LRFD load combinations:
1. TV1 (within distance 2a of building corner)
2. TV2 (more than distance 2a from building corner)
3. VHW
4. VOW4
5. TV5 + VOW5 + VHW (within distance 2a of building corner)
6. VV6 + VOW6 + VHW (more than distance 2a from buildingcorner)
Where TV1, TV2, TV5, TV6, VHW, VOW4, VOW5 and VOW6 aredetermined from Tables B2.1 through B2.4. VHW shall betaken as the larger of VHW1 from Table B2.2 and VHW2 fromTable B2.3. In no case shall VOW be taken as less than280 pounds per linear foot (4.09 kN/m) times the anchorspacing. Where TV is negative in Table B2.1, a value of zero(0) is permitted to be used. Distance “a” is determined fromTable B2.1, Note 4.
For multiple dwellings assigned to Seismic Design CategoryC, and all buildings assigned to Seismic Design Category D0,D1 or D2, connector devices shall also be capable of resistingthe following additional LRFD load combinations:
7. VHS
8. VOS
9. VHS + VOS
Where VHS and VOS are determined from Tables B2.5 andB2.6. In no case shall VOS be taken as less than 280 poundsper linear foot (4.09 kN/m) times the anchor spacing.
Selected connectors shall be capable of resisting the aboveloads acting alone or in combination.
O85573 3.qxd:FPO 85573 3 1/24/08 11:24 AM Page B-5
Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
B-6
LoadingRoofslope
(angle)2
Roofspan(ft)3
aDimension
(ft)4
Exposure category, basic wind speed (mph) and velocity pressure (psf)
85B 90B 100B 110B 120B 130B 140B 150B 166B 179B 192B
85C 90C 100C 110C 120C 130C 140C 150C 163C
85D 90D 100D 110D 120D 130D 140D 150D
11.51 12.90 15.95 19.28 22.94 26.92 31.79 37.41 43.90 50.91 58.45
TV1, TV5Use in loadcombinations
1 and 51.6W+0.9D
end condition(within 2a of
buildingcorner)
0:12to
1:12(0-5
degrees)
20 3 66 90 143 201 265 334 419 517 631 753 884
30 3 99 135 215 302 398 502 629 776 946 1129 1327
40 4 131 180 286 402 530 669 839 1035 1261 1506 1769
4.4:12(20
degrees)
20 3 75 101 157 217 284 357 446 549 667 796 933
30 3 111 149 232 323 423 532 664 818 995 1186 1391
40 4 146 196 307 427 559 703 879 1083 1317 1571 1843
7:12(30
degrees)
20 3 -54 -44 -22 1 27 55 89 129 175 224 278
30 3 -85 -71 -40 -6 32 72 122 180 246 318 395
40 4 -119 -101 -61 -17 31 83 147 221 306 398 497
12:12(45
degrees)
20 3 -65 -57 -38 -18 4 28 58 92 131 174 219
30 3 -111 -100 -75 -49 -20 12 51 95 147 203 263
40 4 -165 -152 -125 -94 -61 -24 20 71 130 194 263
Add for each foot of roofoverhang span 25 29 37 47 57 68 82 98 116 135 156
TV2, TV6Use in load
combinations2 and 6
1.6W+0.9Dinterior condition(at least 2a frombuilding corner)
Allroof
slopes
20 70 95 149 208 274 344 431 531 647 772 906
30 86 121 198 281 373 473 595 736 899 1075 1264
40 101 146 244 351 469 597 754 935 1144 1370 1613
Add for each foot of roofoverhang span 13 15 20 26 32 39 47 57 68 80 93
Table B2.1Wind TV (lb/conn LRFD)1, 5
For SI: 1 in. = 25.4 mm; 1 ft. = 0.3048 m; 1 mph = 0.4470 m/s; 1 psf = 0.0479 kN/m2; I lb. = 4.448 N1 A positive tabulated value indicates an uplift load, a negative value is acting downward and is permitted to be taken as zero for connection design.
Negative values are provided for interpolation purposes.2 For intermediate roof slopes use the larger tabulated value, or determine the value by interpolation.3 For intermediate roof spans use the larger tabulated span, or determine the value by interpolation.4 Distance “a” is 10% of the least horizontal dimension of the building or 0.4 times the mean roof height, whichever is smaller, but not less than 3 feet
(914 mm).5 Tabulated loads are based on a connection spacing of 12 inches (305 mm). For other spacings, multiple value from table by desired connection
spacing in inches (mm) and divide by 12 (305).
O85573 3.qxd:FPO 85573 3 1/24/08 11:24 AM Page B-6
B-7
Appendix B
LoadingRoofslope
(angle)2
Sidewalllength, L(parallelto ridge)
(ft)3
Exposure category, basic wind speed (mph) and velocity pressure (psf)
85B 90B 100B 110B 120B 130B 140B 150B 166B 179B 192B
85C 90C 100C 110C 120C 130C 140C 150C 163C
85D 90D 100D 110D 120D 130D 140D 150D
11.51 12.90 15.95 19.28 22.94 26.92 31.79 37.41 43.90 50.91 58.45
VHW1Use largerof VHW1
and VHW2in load
combinations3, 5 and 6
1.6W
0:12 to 1:12(0-5
degrees)4
20 286 320 396 479 569 668 789 929 1090 1264 1451
40 276 310 383 463 551 646 763 898 1054 1223 1404
60 276 310 383 463 551 646 763 898 1054 1223 1404
4.4:12(20
degrees)4
20 355 398 492 595 708 830 980 1154 1354 1570 1803
40 334 374 463 559 665 781 922 1085 1273 1476 1695
60 334 374 463 559 665 781 922 1085 1273 1476 1695
7:12(30
degrees)5
20 377 422 522 631 751 881 1040 1224 1436 1666 1912
40 388 435 538 650 774 908 1073 1262 1481 1718 1972
60 428 479 593 717 853 1000 1181 1390 1631 1892 2172
12:12(45
degrees)5
20 402 450 557 673 800 939 1109 1305 1532 1777 2040
40 443 496 614 742 882 1035 1223 1439 1689 1958 2248
60 511 573 708 856 1019 1195 1411 1661 1949 2260 2595
Table B2.2 Wind VHW1 Wind Perpendicular to Ridge (lb/conn LRFD)1, 6
For SI: 1 in. = 25.4 mm; 1 ft. = 0.3048 m; 1 mph = 0.4470 m/s; 1 psf = 0.0479 kN/m2; I lb. = 4.448 N1 Tabulated loads are based on a wall floor-to-ceiling clear height of 10 feet (3.0 m) for the first and second stories. Loads are permitted to be reduced
by multiplying by 0.91 where the average wall floor-to-ceiling clear height of the first and second stories does not exceed 9 feet (2.7 m).2 For intermediate roof slopes use the larger tabulated value, or determine the value by interpolation.3 For intermediate values of building sidewall length, L, use the value for the larger tabulated building dimension, or determine by interpolation.4 Tabulated loads are based on a diaphragm aspect ratio, L/W of 2. Tabulated values are permitted to be reduced by multiplying by 0.50 for a
diaphragm aspect ratio, L/W, of 1, and by 0.25 for a diaphragm aspect ratio of 0.5. Interpolation for other values of aspect ratios, L/W, between 2and 0.5 is permitted.
5 Reduction of tabulated loads based on diaphragm aspect ratio is not permitted.6 Tabulated loads are based on a connection spacing of 12 inches (305 mm). For other spacings, multiple value from table by desired connection
spacing in inches (mm) and divide by 12 (305).
O85573 3.qxd:FPO 85573 3 1/24/08 11:24 AM Page B-7
Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
B-8
LoadingRoofslope
(angle)2
Endwalllength, W
(perpendicularto ridge)(ft)3,4
Exposure category, basic wind speed (mph) and velocity pressure (psf)
85B 90B 100B 110B 120B 130B 140B 150B 166B 179B 192B
85C 90C 100C 110C 120C 130C 140C 150C 163C
85D 90D 100D 110D 120D 130D 140D 150D
11.51 12.90 15.95 19.28 22.94 26.92 31.79 37.41 43.90 50.91 58.45
VHW2Use largerof VHW1
and VHW2in load
combinations3, 5 and 6
1.6W
0:12 to 1:12(0-5
degrees)
20 261 293 362 437 521 611 721 849 996 1155 1326
40 250 280 346 419 498 585 690 812 953 1105 1269
60 255 285 353 427 508 596 703 828 971 1126 1293
4.4:12(20
degrees)
20 278 311 385 466 554 650 768 903 1060 1229 1411
40 280 314 388 469 558 655 774 910 1068 1239 1422
60 300 336 416 502 598 701 828 975 1144 1326 1523
7:12(30
degrees)
20 291 326 403 487 580 680 803 945 1109 1286 1477
40 307 344 425 514 611 718 847 997 1170 1357 1558
60 342 383 474 573 682 800 945 1112 1305 1513 1738
12:12(45
degrees)
20 316 355 438 530 630 740 874 1028 1207 1399 1606
40 353 396 489 592 704 826 975 1148 1347 1562 1793
60 412 462 571 691 822 964 1139 1340 1572 1823 2093
Table B2.3 Wind VHW2 Wind Parallel to Ridge (lb/conn LRFD)1,5
For SI: 1 in. = 25.4 mm; 1 ft. = 0.3048 m; 1 mph = 0.4470 m/s; 1 psf = 0.0479 kN/m2; I lb. = 4.448 N1 Tabulated loads are based on a wall floor-to-ceiling clear height of 10 feet (3.0 m) for the first and second stories. Loads are permitted to be
reduced by multiplying by 0.91 where the average wall floor-to-ceiling clear height of the first and second stories does not exceed 9 feet (2.7 m).2 For intermediate roof slopes use the larger tabulated value, or determine the value by interpolation.3 For intermediate values of building endwall length, W, use tabulated plan dimension that results in larger VHW2, or determine by interpolation.4 Tabulated loads are based on a diaphragm aspect ratio, W/L, of 2. Tabulated values are permitted to be reduced by multiplying by 0.50 for a
diaphragm aspect ratio, W/L, of 1, and by 0.25 for a diaphragm aspect ratio of 0.5. Interpolation for other values of aspect ratios, W/L, between2 and 0.5 is permitted.
5 Tabulated loads are based on a connection spacing of 12 inches (305 mm). For other spacings, multiple value from table by desired connectionspacing in inches (mm) and divide by 12 (305).
O85573 3.qxd:FPO 85573 3 1/24/08 11:24 AM Page B-8
B-9
Appendix B
LoadingRoofslope
(angle)2
Exposure category, basic wind speed (mph) and velocity pressure (psf)
85B 90B 100B 110B 120B 130B 140B 150B 166B 179B 192B
85C 90C 100C 110C 120C 130C 140C 150C 163C
85D 90D 100D 110D 120D 130D 140D 150D
11.51 12.90 15.95 19.28 22.94 26.92 31.79 37.41 43.90 50.91 58.45
VOW4Use in load
combination 41.6W
Components &Cladding
All roofslopes
(angles)3118 132 163 197 235 276 326 383 450 521 599
VOW5, VOW6Use in load
combinations5 and 61.6W
MWFRS
0:12 to 1:12(0-5 degrees) 43 49 60 72 86 101 120 141 165 191 220
4.4:12(20 degrees) 56 63 78 94 112 131 155 183 214 248 285
7:12 to 12:12(30-45 degrees) 51 57 70 85 101 118 140 165 193 224 257
Table B2.4 Wind VOW (lb/conn LRFD)1, 4
For SI: 1 in. = 25.4 mm; 1 mph = 0.4470 m/s; 1 psf = 0.0479 kN/m2; I lb. = 4.448 N1 Tabulated loads are based on a wall floor-to-ceiling clear height of 10 feet (3.0 m) for the first and second stories. Loads are permitted to be reduced
by multiplying by 0.90 where the average wall floor-to-ceiling clear height of the first and second stories does not exceed 9 feet (2.7 m).2 Interpolation between tabulated roof slopes is permitted.3 Tabulated components and cladding loads are permitted to be reduced by multiplying by 0.91 for roof slopes less than or equal to 2.2:12
(10 degrees).4 Tabulated loads are based on a connection spacing of 12 inches (305 mm). For other spacings, multiple value from table by desired connection
spacing in inches (mm) and divide by 12 (305).
O85573 3.qxd:FPO 85573 3 1/24/08 11:24 AM Page B-9
Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
B-10
LoadingMaximum
concrete wallweight (psf)2
Ratio of larger buildingplan dimension to smallerbuilding plan dimension3
Larger building plandimension (ft)4
Seismic design category andmaximum SDS value (g )5
C D0 D1 D2
0.50 0.67 0.83 1.00
VHS
Use in loadcombinations
7 and 9E
56 220 169 227 281 338
40 229 306 379 457
60 288 386 478 576
76 220 188 252 312 376
40 247 331 410 494
60 307 411 509 613
100 220 210 282 349 421
40 270 361 448 539
60 329 441 546 658
125 220 234 313 388 467
40 293 393 486 586
60 352 472 585 705
Table B2.5 Seismic VHS (lb/conn LRFD)1, 6
For SI: 1 in. = 25.4 mm; 1 ft. = 0.3048 m; 1 psf = 0.0479 kN/m2; I lb. = 4.448 N1 Tabulated loads are based on a wall floor-to-ceiling clear height of 10 feet (3.0 m) for the first and second stories. Loads are permitted to be reduced
by multiplying by 0.91 where the average wall floor-to-ceiling clear height of the first and second stories does not exceed 9 feet (2.7 m).2 Tabulated weight includes concrete weight only. 13 psf (0.62 kN/m2) additional weight is permitted for combined interior and exterior wall finishes.
See Table 2.1 for weights of walls within the scope of this Standard.3 Tabulated loads are based on a diaphragm aspect ratio of 2 (ratio of larger plan dimension to smaller plan dimension). Tabulated values are permitted
to be reduced by multiplying by 0.60 for a diaphragm aspect ratio of 1. Interpolation between aspect ratios of 2 and 1 is permitted.4 For intermediate larger building plan dimensions, use the value for the next larger tabulated building dimension, or determine by interpolation.5 Interpolation between tabulated SDS values is permitted. For Seismic Design Category C, interpolation between 0.50 and the lower-bound threshold
SDS value of 0.33 is permitted.6 Tabulated loads are based on a connection spacing of 12 inches (305 mm). For other spacings, multiple value from table by desired connection
spacing in inches (mm) and divide by 12 (305).
O85573 3.qxd:FPO 85573 3 1/24/08 11:24 AM Page B-10
B-11
Appendix B
Maximum concretewall weight (psf)2
Seismic design category and maximum SDS value (g )3
C D0 D1 D2
0.50 0.67 0.83 1.00
VOSUse in load
combinations8 and 9
E
56 138 185 229 276
76 178 239 295 356
100 226 303 375 452
125 276 370 458 552
Table B2.6 Seismic VOS (lb/conn LRFD)1, 4
For SI: 1 in. = 25.4 mm; 1 psf = 0.0479 kN/m2; I lb. = 4.448 N1 Tabulated loads are based on a wall floor-to-ceiling clear height of 10 feet (3.0 m) for the first and second stories. Loads are
permitted to be reduced by multiplying by 0.95 where the average wall floor-to-ceiling clear height of the first and secondstories does not exceed 9 feet (2.7 m).
2 Tabulated weight includes concrete weight only. 13 psf (0.62 kN/m2) additional weight is permitted for combined interior andexterior wall finishes. See Table 2.1 for weights of walls within the scope of this Standard.
3 Interpolation between tabulated SDS values is permitted. For Seismic Design Category C, interpolation between 0.50 and thelower-bound threshold SDS value of 0.33 is permitted.
4 Tabulated loads are based on a connection spacing of 12 inches (305 mm). For other spacings, multiple value from table bydesired connection spacing in inches (mm) and divide by 12 (305).
B.4 DETAIL 3 LRFD LOAD TABLESFigure B.3 Detail 3 is for the connection of a light-framedroof to the top of a concrete wall similar to the connectiondetails of Figures 6.11 through 6.14. Three loads act on thisconnection simultaneously (Figure B.3). One connectiondevice shall be capable of resisting all three loads, oralternately two or more connection devices shall bepermitted.
Figure B.3. Detail 3 loads.
DETAIL 3 LRFD LOAD COMBINATIONSFor all buildings, connector devices shall be capable ofresisting not less than the following LRFD load combinations:1. TV1 (within distance 2a of building corner)2. TV2 (more than distance 2a from building corner)3. VHW
4. VOW4
5. TV5 + VOW5 + VHW (within distance 2a of building corner)6. TV6 + VOW6 + VHW (more than distance 2a from building
corner)
Where TV1, TV2, TV5, TV6, VHW, VOW4, VOW5 and VOW6 aredetermined from Tables B3.1 through B3.4. VHW shall betaken as the larger of VHW1 from Table B3.2 and VHW2 fromTable B3.3. In no case shall VOW be taken as less than 280pounds per linear foot (4.09 kN/m) times the anchor spacing.Where TV is negative in Table B3.1, a value of zero (0) ispermitted to be used. Distance “a” is determined from TableB3.1, Note 4.
For multiple dwellings assigned to Seismic Design CategoryC, and all buildings assigned to Seismic Design Category D0,D1 or D2, connector devices shall also be capable of resistingthe following additional LRFD load combinations:7. VHS
8. VOS
9. VHS + VOS
Where VHS and VOS are determined from Tables B3.5 andB3.6. In no case shall VOS be taken as less than 280 poundsper linear foot (4.09 kN/m) times the anchor spacing.
Selected connectors shall be capable of resisting the aboveloads acting alone or in combination.
O85573 3.qxd:FPO 85573 3 1/24/08 11:24 AM Page B-11
Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
B-12
LoadingRoofslope
(angle)2
Roofspan(ft)3
aDimension
(ft)4
Exposure category, basic wind speed (mph) and velocity pressure (psf)
85B 90B 100B 110B 120B 130B 140B 150B 166B 179B 192B
85C 90C 100C 110C 120C 130C 140C 150C 166C
85D 90D 100D 110D 120D 130D 140D 150D
11.51 12.90 15.95 19.28 22.94 26.92 31.79 37.41 43.90 50.91 58.45
TV1, TV5Use in loadcombinations
1 and 51.6W+0.9D
EndCondition
(within 2a ofbuildingcorner)
0:12to
1:12(0-5
degrees)
20 3 66 90 143 201 265 334 419 517 631 753 884
30 3 99 135 215 302 398 502 629 776 946 1129 1327
40 4 131 180 286 402 530 669 839 1035 1261 1506 1769
4.4:12(20
degrees)
20 3 75 101 157 217 284 357 446 549 667 796 933
30 3 111 149 232 323 423 532 664 818 995 1186 1391
40 4 146 196 307 427 559 703 879 1083 1317 1571 1843
7:12(30
degrees)
20 3 -54 -44 -22 1 27 55 89 129 175 224 278
30 3 -85 -71 -40 -6 32 72 122 180 246 318 395
40 4 -119 -101 -61 -17 31 83 147 221 306 398 497
12:12(45
degrees)
20 3 -65 -57 -38 -18 4 28 58 92 131 174 219
30 3 -111 -100 -75 -49 -20 12 51 95 147 203 263
40 4 -165 -152 -125 -94 -61 -24 20 71 130 194 263
Add for each foot of roofoverhang span 25 29 37 47 57 68 82 98 116 135 156
TV2, TV6Use in load
combinations2 and 6
1.6W+0.9Dinterior
condition(at least 2a frombuilding corner)
Allroof
slopes
20 70 95 149 208 274 344 431 531 647 772 906
30 86 121 198 281 373 473 595 736 899 1075 1264
40 101 146 244 351 469 597 754 935 1144 1370 1613
Add for each foot of roofoverhang span 13 15 20 26 32 39 47 57 68 80 93
Table B3.1Wind TV (lb/conn LRFD)1, 5
For SI: 1 in. = 25.4 mm; 1 ft. = 0.3048 m; 1 mph = 0.4470 m/s; 1 psf = 0.0479 kN/m2; I lb. = 4.448 N1 A positive tabulated value indicates an uplift load, a negative value is acting downward and is permitted to be taken as zero for connection
design. Negative values are provided for interpolation purposes.2 For intermediate roof slopes use the larger tabulated value, or determine the value by interpolation.3 For intermediate roof spans use the next larger tabulated span, or determine the value by interpolation.4 Distance “a” is 10% of the least horizontal dimension of the building or 0.4 times the mean roof height, whichever is smaller, but not less than 3 feet
(914 mm).5 Tabulated loads are based on a connection spacing of 12 inches (305 mm). For other spacings, multiple value from table by desired connection
spacing in inches (mm) and divide by 12 (305).
O85573 3.qxd:FPO 85573 3 1/24/08 11:24 AM Page B-12
B-13
Appendix B
LoadingRoofslope
(angle)2
Sidewalllength L,(parallelto ridge)
(ft)3
Exposure category, basic wind speed (mph) and velocity pressure (psf)
85B 90B 100B 110B 120B 130B 140B 150B 166B 179B 192B
85C 90C 100C 110C 120C 130C 140C 150C 163C
85D 90D 100D 110D 120D 130D 140D 150D
11.51 12.90 15.95 19.28 22.94 26.92 31.79 37.41 43.90 50.91 58.45
VHW1Use largerof VHW1
and VHW2in load
combinations3, 5 and 6
1.6W
0:12 to 1:12(0-5
degrees)4
20 80 90 111 134 159 187 221 260 305 354 406
40 75 84 104 126 150 176 208 244 287 332 382
60 75 84 104 126 150 176 208 244 287 332 382
4.4:12(20
degrees)4
20 111 124 154 186 221 259 306 361 423 491 563
40 104 117 145 175 208 244 288 339 398 461 530
60 104 117 145 175 208 244 288 339 398 461 530
7:12(30
degrees)5
20 135 152 187 227 270 316 374 440 516 598 687
40 168 188 232 281 334 392 463 545 640 742 852
60 205 230 284 343 408 479 566 666 781 906 1040
12:12(45
degrees)5
20 194 217 269 325 386 453 535 630 739 857 984
40 281 315 389 470 560 657 775 913 1071 1242 1426
60 374 420 519 627 746 876 1034 1217 1428 1656 1901
Table B3.2 Wind VHW1 Wind Perpendicular to Ridge (lb/conn LRFD)1, 6
For SI: 1 in. = 25.4 mm; 1 ft. = 0.3048 m; 1 mph = 0.4470 m/s; 1 psf = 0.0479 kN/m2; I lb. = 4.448 N1 Tabulated loads are based on a top story wall floor-to-ceiling clear height of 10 feet (3.0 m). Loads are permitted to be reduced by multiplying
by 0.90 where the top story wall floor-to-ceiling clear height does not exceed 8 feet (2.4 m), or by 0.95 where the top story wall floor-to-ceiling clear height does not exceed 9 feet (2.7 m).
2 For intermediate roof slopes use the larger tabulated value, or determine the value by interpolation.3 For intermediate values of building sidewall length, L, use the value for the larger tabulated building dimension, or determine by interpolation.4 Tabulated loads are based on a diaphragm aspect ratio, L/W of 2. Tabulated values are permitted to be reduced by multiplying by 0.50 for a
diaphragm aspect ratio, L/W, of 1, and by 0.25 for a diaphragm aspect ratio of 0.5. Interpolation for other values of aspect ratios, L/W,between 2 and 0.5 is permitted.
5 Reduction of tabulated loads based on diaphragm aspect ratio is not permitted.6 Tabulated loads are based on a connection spacing of 12 inches (305 mm). For other spacings, multiple value from table by desired connection
spacing in inches (mm) and divide by 12 (305).
O85573 3.qxd:FPO 85573 3 1/24/08 11:24 AM Page B-13
Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
B-14
LoadingRoofslope
(angle)2
Endwelllength, W
(perpendicularto ridge)(ft)3, 4
Exposure category, basic wind speed (mph) and velocity pressure (psf)
85B 90B 100B 110B 120B 130B 140B 150B 166B 179B 192B
85C 90C 100C 110C 120C 130C 140C 150C 163C
85D 90D 100D 110D 120D 130D 140D 150D
11.51 12.90 15.95 19.28 22.94 26.92 31.79 37.41 43.90 50.91 58.45
VHW2Use largerof VHW1
and VHW2in load
combinations3, 5 and 6
1.6W
0:12 to 1:12(0-5
degrees)
20 85 96 118 143 170 199 235 277 325 377 433
40 85 95 117 142 169 198 234 275 323 374 430
60 89 100 124 150 178 209 247 290 341 395 454
4.4:12(20
degrees)
20 102 114 141 171 203 238 282 331 389 451 518
40 115 129 159 192 229 268 317 373 438 508 583
60 135 151 187 225 268 315 372 437 513 595 684
7:12(30
degrees)
20 115 129 159 192 229 269 317 373 438 508 583
40 139 156 193 233 278 326 385 453 532 616 708
60 173 193 239 289 344 404 477 561 658 764 877
12:12(45
degrees)
20 140 157 195 235 280 328 388 456 536 621 713
40 186 208 257 311 370 434 513 604 709 822 943
60 243 272 336 407 484 568 670 789 926 1074 1233
Table B3.3 Wind VHW2 Wind Parallel to Ridge (lb/conn LRFD)1, 5
For SI: 1 in. = 25.4 mm; 1 ft. = 0.3048 m; 1 mph = 0.4470 m/s; 1 psf = 0.0479 kN/m2; I lb. = 4.448 N1 Tabulated loads are based on a top story wall floor-to-ceiling clear height of 10 feet (3.0 m). Loads are permitted to be reduced by multiplying by
0.90 where the top story wall floor-to-ceiling clear height does not exceed 8 feet (2.4 m), or by 0.95 where the top story wall floor-to-ceiling clearheight does not exceed 9 feet (2.7 m).
2 For intermediate roof slopes use the larger tabulated value, or determine the value by interpolation.3 For intermediate values of building endwall length, W, use tabulated plan dimension that results in larger VHW2, or determine by interpolation.4 Tabulated loads are based on a diaphragm aspect ratio, W/L, of 2. Tabulated values are permitted to be reduced by multiplying by 0.50 for a
diaphragm aspect ratio, W/L, of 1, and by 0.25 for a diaphragm aspect ratio of 0.5. Interpolation for other values of aspect ratios, W/L, between2 and 0.5 is permitted.
5 Tabulated loads are based on a connection spacing of 12 inches (305 mm). For other spacings, multiple value from table by desired connectionspacing in inches (mm) and divide by 12 (305).
O85573 3.qxd:FPO 85573 3 1/24/08 11:24 AM Page B-14
B-15
Appendix B
LoadingRoofslope
(angle)2
Exposure category, basic wind speed (mph) and velocity pressure (psf)
85B 90B 100B 110B 120B 130B 140B 150B 166B 179B 192B
85C 90C 100C 110C 120C 130C 140C 150C 163C
85D 90D 100D 110D 120D 130D 140D 150D
11.51 12.9 15.95 19.28 22.94 26.92 31.79 37.41 43.9 50.91 58.45
VOW4Use in load
combination 41.6W
components& cladding
All roofslopes
(angle)3118 132 163 197 235 276 326 383 450 521 599
VOW5, VOW6Use in load
combinations5 and 61.6W
MWFRS
0:12to 1:12
(0-5 degrees)43 49 60 72 86 101 120 141 165 191 220
4.4:12(20 degrees) 56 63 78 94 112 131 155 183 214 248 285
7:12to 12:12
(30-45 degrees)51 57 70 85 101 118 140 165 193 224 257
Table B3.4 Wind VOW (lb/conn LRFD)1, 4
For SI: 1 in. = 25.4 mm; 1 mph = 0.4470 m/s; 1 psf = 0.0479 kN/m2; I lb. = 4.448 N1 Tabulated loads are based on a top story wall floor-to-ceiling clear height of 10 feet (3.0 m). Loads are permitted to be reduced by multiplying by 0.80
where the top story wall floor-to-ceiling clear height does not exceed 8 feet (2.4 m), or by 0.90 where the top story wall floor-to-ceiling clear height doesnot exceed 9 feet (2.7 m).
2 For intermediate roof slopes use the larger tabulated value, or determine the value by interpolation.3 Tabulated components and cladding loads are permitted to be multiplied by 0.91 for roof slopes less than or equal to 2.12:12 (10 degrees).4 Tabulated loads are based on a connection spacing of 12 inches (305 mm). For other spacings, multiple value from table by desired connection spacing in
inches (mm) and divide by 12 (305).
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LoadingMaximum
concrete wallweight (psf)2
Ratio of larger buildingplan dimension to smallerbuilding plan dimension3
Larger buildingplan dimension
(ft)4
Seismic design category and maximum SDS value (g )5
C D0 D1 D2
0.50 0.67 0.83 1.00
VHSUse inload
combinations7 and 9
E
56 220 108 145 179 21640 145 195 241 29160 183 245 303 365
76 220 127 170 210 25340 164 220 272 32860 201 270 334 403
100 220 165 222 275 33140 203 272 337 40660 240 322 399 481
125 220 172 231 286 34540 210 281 348 42060 247 331 410 494
Table B3.5 Seismic VHS (lb/conn LRFD)1, 6
For SI: 1 in. = 25.4 mm; 1 ft. = 0.3048 m; 1 psf = 0.0479 kN/m2; I lb. = 4.448 N1 Tabulated loads are based on a top story wall floor-to-ceiling clear height of 10 feet (3.0 m). Loads are permitted to be reduced by
multiplying by 0.90 where the top story wall floor-to-ceiling clear height does not exceed 8 feet (2.4 m), or by 0.95 where the top storywall floor-to-ceiling clear height does not exceed 9 feet (2.7 m).
3 Tabulated loads are based on a diaphragm aspect ratio of 2 (ratio of larger plan dimension to smaller plan dimension). Tabulated values arepermitted to be reduced by multiplying by 0.60 for a diaphragm aspect ratio of 1. Interpolation between aspect ratios of 2 and 1 ispermitted.
4 For intermediate larger building plan dimensions use the value for the larger tabulated building dimension, or determine by interpolation.5 Interpolation between tabulated SDS values is permitted. For Seismic Design Category C, interpolation between 0.50 and the lower-bound
threshold SDS value of 0.33 is permitted.6 Tabulated loads are based on a connection spacing of 12 inches (305 mm). For other spacings, multiple value from table by desired connec-
tion spacing in inches (mm) and divide by 12 (305).
Maximum concretewall weight (psf)2
Seismic design category and maximum SDS value (g )3
C D0 D1 D2
0.50 0.67 0.83 1.00
VOSUse in load
combinations8 and 9
E
56 138 185 229 276
76 178 239 295 356
100 226 303 375 452
125 276 370 458 552
Table B3.6 Seismic VOS (lb/conn LRFD)1,4
For SI: 1 in. = 25.4 mm; 1 psf = 0.0479 kN/m2; I lb. = 4.448 N1 Tabulated loads are based on a top story wall floor-to-ceiling clear height of 10 feet (3.0 m). Loads are permitted to be reduced by
multiplying by 0.80 where the top story wall floor-to-ceiling clear height does not exceed 8 feet (2.4 m), or by 0.90 where the top storywall floor-to-ceiling clear height does not exceed 9 feet (2.7 m).
2 Tabulated weight includes concrete weight only. 13 psf (0.62 kN/m2) additional weight is permitted for combined interior and exterior wallfinishes. See Table 2.1 for weights of walls within the scope of this Standard.
3 Interpolation between tabulated SDS values is permitted. For Seismic Design Category C, interpolation between 0.50 and the lower-boundthreshold SDS value of 0.33 is permitted.
4 Tabulated loads are based on a connection spacing of 12 inches (305 mm). For other spacings, multiple value from table by desired connec-tion spacing in inches (mm) and divide by 12 (305).
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C-1
Commentary toPrescriptive Design of Exterior ConcreteWalls for
One- and Two-Family DwellingsPCA 100-2007
This commentary is not a part of Prescriptive Design of
Exterior Concrete Walls for One- and Two-Family Dwellings.
It is included to provide background information on some of
the provisions. The sections in the commentary are numbered
to correspond to the sections of the standard to which they
relate. Since background information is not necessary for
every section in the standard, there are gaps in the
numbering sequence in the commentary.
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Appendix CCommentary
CHAPTER 1 COMMENTARY –GENERAL
C1.1 SCOPEThis Standard presents prescriptive criteria for the design andconstruction of one- and two-story detached, one-and two-family dwellings and multiple dwellings, including town-houses, with exterior concrete walls. Walls must becast-in-place using either removable or stay-in-place formingsystems. It provides requirements, primarily in tables andfigures, that will permit the exterior walls of typical homes tobe constructed of concrete without the added expense ofhiring a registered design professional. Where calculationshave been developed as a basis for this Standard, the calcu-lations are based on the strength (resistance) requirements ofACI 318 [C1.1] and the loading requirements of ASCE 7[C1.2], using model buildings with common configurations.These standards are generally enforced in contemporaryU.S. building codes governing residential construction.Some aspects of detailing and load paths are taken fromhistorically used residential construction practice rather thanthese standards.
This Standard is not applicable to all possible conditions ofuse and is subject to the limitations set forth in Section 1.2and Table 1.1. These limits should be carefully understoodas they define important constraints on the use of the Stan-dard. The Standard is not intended to restrict the use ofabove minimum requirements based on sound judgment oruse of exact engineering analysis of specific applications thatmay result in improved designs and economy.
This Standard was developed on the basis that the exteriorconcrete walls would be used in combination with floors,roofs and interior walls of light-framed construction com-plying with the prescriptive requirements of the InternationalResidential Code (IRC) [C1.3], the performance requirementsof the of the International Building Code (IBC) [C1.4] orBuilding Construction and Safety Code NFPA 5000 [C1.5],or other codes having similar requirements. Light-framedconstruction includes members of wood or cold-formed
steel. Unit dead load limitations of Table 1.1 for floor androof-ceiling assemblies are applicable to all buildingsconstructed in accordance with this Standard. They areconsistent with the unit dead load limitations of the IRC;however, the IRC limitation is only applicable to townhouses(multiple dwellings) assigned to Seismic Design Category C,and all buildings assigned to Seismic Design Category D0,D1 or D2.
While this Standard does not address the use of interiorwalls of concrete construction, in some cases such walls canbe used without adversely affecting the performance ofbuildings designed in accordance with this Standard. Interiorconcrete walls that are supported by footings may be used indetached one- and two-family dwellings assigned to SeismicDesign Category A, B or C, and in multiple dwellingsassigned to Seismic Design Category A or B. Interiorconcrete walls must be designed in accordance with theapplicable building code, or in the absence of a code inaccordance with ACI 318 [C1.1].
It is intended that portions of the building and aspects ofconcrete construction not specifically addressed by thisStandard be designed and constructed in accordance withthe applicable building code, such as the IRC, IBC, NFPA5000, or a similar building code. Where there is no applic-able building code, provisions of one of the heretofore-mentioned codes should be followed to assure that thecompleted structure is capable of withstanding the loadsand forces to which it may be subjected during its life. At aminimum, the portions of the building of concrete construc-tion should be designed and constructed to comply withrequirements of ACI 318 [C1.1] and ASCE 7 [C1.2].
C1.2 LIMITATIONS ONUSEThe requirements set forth in this Standard apply only tothe construction of houses that meet the limits set forth inSection 1.2 and Table 1.1. The applicability limits are neces-sary for defining reasonable boundaries to the conditionsthat must be considered in developing prescriptive construc-tion requirements. This Standard, however, does not limit
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Appendix C – Commentaries
the application of alternative methods or materials throughengineering design by a registered design professional.
The applicability limits are based on industry convention andexperience. Detailed applicability limits were documented inthe process of developing prescriptive design requirementsfor various elements of the structure. In some cases, engi-neering sensitivity analyses were performed to help defineappropriate limits.
The applicability limits strike a reasonable balance amongengineering theory, available test data, and proven fieldpractices for typical residential construction applications.They are intended to prevent misapplication while at thesame time addressing a reasonably large percentage of newhousing conditions. Special consideration is directed towardthe following items related to the applicability limits.
Building Geometry
The provisions in this Standard apply to detached one- ortwo-family dwellings, and multiple dwellings, with maximumbuilding plan dimensions of 60 feet (18.3 m) that are notmore than two stories in height above grade, excluding abasement that is not considered a story above grade plane.
For multiple dwellings assigned to Seismic Design Category Cand all buildings assigned to Seismic Design Category D thereare additional limitations. The maximum aspect ratio of 2:1in item #1 of Section 1.2.2 is based on the footprint of thebuilding, not of an individual dwelling unit within the build-ing. In addition, the building must be rectangular in plan,which means that offsets and buildings made up of two ormore attached rectangles are not permitted, except as notedbelow. Application to homes with complex architecturalconfigurations is subject to careful interpretation and soundjudgment by the user and design support may be required.
Two exceptions to the required rectangular footprint areprovided in order to accommodate commonly occurringbuilding configurations. The first exception permits a singlestory attached garage to be a separate rectangle. This isacceptable because a one story attached garage of moderatesize will generally not significantly affect the performance ofthe adjoining house, provided that both the garage and thehouse are designed in accordance with the requirements ofthe standard. A larger or two-story garage could affect theperformance due to larger mass and greater effect onstiffness and force distribution.
The second exception permits offsets in exterior wallsprovided that chord members at the main wall line are
designed. The concept is based on offsets permitted in light-framed wood construction. The chord forces and detailingrequirements can be significant, making it difficult to providea prescriptive chord member and connection. Design willneed to include all forces acting on the chord member andconnections, including gravity dead and live loads.
Site Conditions
Snow loads are typically given in a ground snow load mapsuch as that provided in ASCE 7 [C1.2] or by local practice.The 0 to 70 psf (0 to 3.35 kN/m2) ground snow load used inthis Standard covers approximately 90 percent of the UnitedStates, which includes the majority of the houses that areexpected to be covered by this Standard. In areas with higherground snow loads, this document cannot be used and aregistered design professional should be consulted.
All areas of the United States fall within the 85 to 150 mph(38 to 67 m/s) range of 3-second gust basic wind speeds[C1.2]. Houses subject to flood loading or storm surgecannot be designed with this document and a registereddesign professional should be consulted. Requirements ofthe National Flood Insurance Program, administered by theFederal Emergency Management Agency, ASCE 7 [C1.2] andASCE 24 [C1.6] should also be employed for structuressubject to flood loading.
Detached one- and two-family dwellings, and multipledwellings, designed and constructed in accordance with thisStandard are limited to those assigned to Seismic DesignCategory A, B, C, D0, D1, or D2 [C1.2], and the other limita-tions of Section 1.2 and Table 1.1. Buildings of otheroccupancies assigned to Seismic Design Category A andcomplying with all the limitations may be designed andconstructed in accordance with this Standard. However,users of the Standard should be aware that the 40 psf(1.92 kN/m2) maximum floor live load limitation of Table 1.1effectively restricts the height to one story buildings erectedon slabs-on-grade since most building codes require higherfloor live loads for other occupancies.
Soil borings are rarely required for residential constructionexcept where there are known risks or a history of problems(i.e., organic deposits, landfills, expansive soils) associatedwith building in certain areas. The minimum presumptivesoil-bearing value of 1,500 psf (71.85 kN/m2) is based ontypical soil conditions in the United States except in areas ofhigh risk or where local experience or geotechnical investiga-tion proves otherwise.
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Loads
If the basic wind speed velocities in the building code of thejurisdiction where this Standard is to be used are based onfastest-mile wind speeds, the designer should convert thosewind speeds to 3-second gust wind speeds in accordancewith Table C1.1 for use with the tables in this Standard.
C1.4 FORMING SYSTEM LIMITATIONSRegardless of the forms used, concrete walls having cross-sectional shapes and dimensions within the limitations setforth in Table 2.1, Figure 1.3, Figure 2.1, Figure 2.2, andFigure 2.3 are permitted to be designed and constructed inaccordance with this Standard. Removable forms are usuallyconstructed of wood, aluminum, steel, or combinations ofthese materials and typically produce flat wall cross-sections.Some removable form systems incorporate rigid foam plasticinsulation that stay in place after the forms are removed toprovide insulation value to the wall. Stay-in-place formingsystems are typically constructed of plastic, rigid foam plastic,composite of cement and plastic foam, composite of cementand wood fibers or chips. Most stay-in-place forms are madewith rigid foam plastic and are commonly known asInsulating Concrete Forms (ICFs).
This Standard addresses three categories of stay-in-placeform systems based on the resulting cross-sectional shape ofthe formed concrete wall. See Figure 1.3. The shape of theconcrete wall may be better understood by visualizing theform stripped away from the concrete, thereby exposing it toview. There are three categories of stay-in-place wall forms:flat, grid, and post-and-beam. The grid wall type is furthercategorized into waffle-grid and screen-grid wall systems.These classifications are provided solely to ensure that thedesign tables in this Standard are applied to the stay-in-placewall systems as the scope intends. The post-and-beam stay-in-place wall system is not included in the Standard becauseit requires a different engineering analysis.
C1.5 CONSTRUCTIONDOCUMENTSTable C1.2 contains some items that should be included onconstruction documents, if applicable to a specific project.The table may also be useful as a checklist when thisstandard is being used to design a building.
C1.6 DEFINITIONSThe definitions in this Standard are provided because certainterms are likely to be unfamiliar to the home building trade.Additional definitions that warrant technical explanation aredefined below since they are used in the Commentary.
Permeance: The permeability of a porous material; ameasure of the ability of moisture to migrate through amaterial.
Presumptive: Formation of a judgment on probablegrounds until further evidence is received.
Registered Design Professional: An individual who isregistered or licensed to practice their respective designprofession as defined by the statutory requirements of theprofessional registration laws of the state or jurisdiction inwhich the project is to be constructed.
Superplasticizer: A substance added to concrete mixthat improves workability at very low water-cement ratios toproduce high, early-strength concrete. Also referred to ashigh-range, water-reducing admixtures.
REFERENCESC1.1 Building Code Requirements for Structural Concrete
(ACI 318-05) and Commentary (ACI 318R-05).American Concrete Institute, Farmington Hills,Michigan. 2004.
C1.2 Minimum Design Loads for Buildings and OtherStructures, including Supplement No.1,ASCE/SEI 7-05.American Society of Civil Engineers, Reston, Virginia.2005.
C1.3 International Residential Code For One- and Two-Family Dwellings, 2006 Edition. International CodeCouncil (ICC), Falls Church, Virginia. 2006.
C1.4 International Building Code, 2006 Edition. InternationalCode Council (ICC), Falls Church, Virginia. 2006.
C1.5 Building Construction and Safety Code NFPA 5000,2006 Edition. National Fire Protection Association,Quincy, Massachusetts. 2005.
C1.6 Flood Resistant Design and Construction, ASCE/SEI 24-05. American Society of Civil Engineers, Reston,Virginia. 2005.
Table C1.1. Wind Speed Conversions
Fastest Mile (mph) 3-Second Gust (mph)
70 84
75 89
80 95
90 105
100 116
110 126
120 137
130 147
For SI: 1 mph = 0.4470 m/s
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Appendix C – Commentaries
Table C1.2. Information on Construction Documents
Items that should be shownReference section, T(able), Building
Code (BC), or ASCE 7
Site parameters
Basic wind speed and exposure category 1.2, 1.6, T 5.1A – 5.1C, T 5.2, BD, ASCE 7
Ground snow load 1.2, 1.6, T 3.1, BC, ASCE 7
Seismic Design Category 1.2, 1.6, BC, ASCE 7
Design, 5 percent damped, spectral response acceleration atshort period, SDS
BC, ASCE 7
Load-bearing value of soil 1.2, 1.6, BC 3.1.2, T 3.1, BC
Design lateral soil load used for foundation walls 1.2, 1.6, T 3.2, T 3.4 – 3.10, BC
Building parameters
Wind enclosure classification 1.2, 1.6, BC, ASCE 7
Mean roof height used if less than 35 feet (10.7 m) 1.2, 5.1.1, T 5.2, T 7.1A
Type and weight of roof covering 1.2
Type and weight of exterior wall covering 1.2, T 3.1
Area within exterior walls projected onto horizontal plane (forbuildings required to be designed for seismic only)
T 5.5A – T 5.5C, T 5.6A, T 5.6B, T 5.7, T 5.8
Unbalanced backfill height 1.2, 1.6, T 3.2, T 3.4 – 3.10
Concrete structural elements
Location with respect to other members and size, including:thickness, depth, length and height
Portions of exterior concrete walls serving as required solid wallsegments, including length of each segment 5.1, 5.2
For waffle- and screen-grid walls, documentation that concretecross-section will comply with dimensional requirements T 2.1
Indicate any form material required to be removed from waffle-and screen-grid forms to increase concrete section
T 5.4B (note 9), T 7.11 – 7.14 (note 1), T 7.15 – 7.16 (note 1),T 7.18 (notes 1 & 2), T 7.23 – 7.24 (note 1), T 7.25 (note 1)
Concrete
Specified compressive strength of concrete, ø 2.2.5, 3.2.5, 4.1.4
Specified slump 2.2.4, 2.2.6
Reinforcement
ASTM type and Grade or yield strength of reinforcement 2.3.1, 4.1.3
Length of lap splices – for all bars sizes and grades specified 2.5.3
Embedment depth for development of bars in tension 2.5.4
Length of bar extension for standard hooks 2.5.5
Dimensional location of reinforcement within all members,including depth, d, cover and bar spacing 2.5.1, 2.5.2, 3.3, 4.1.7, 5.2.2
Indicate horizontal and vertical reinforcement required toterminate with a standard hook 2.5.5, 4.1.6
Connections to concreteASTM type and grade of anchor bolts, including whether bolthas a head or nut on threaded end 2.3.2
Diameter of bolts, embedment depth and location, includingedge distance, spacing and distance from end of element Figures 6.3 – 6.14
Specifications for proprietary anchors, including required designstrengths 6.4(3), 6.5(3)
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CHAPTER 2 COMMENTARY –GENERAL REQUIREMENTS
C2.1 DIMENSIONS OFWALLSDue to industry variations related to the dimensions of stay-in-place forms, dimensions were standardized (i.e., thickness,width, spacing) to allow for the development of thisStandard. This approach may result in a conservative designfor stay-in-place form systems where thickness and width aregreater than the minimum allowable or the spacing ofvertical cores is less than the maximum allowable. In thesecases, design in accordance with ACI 318 [C2.1] may bemore economical.
C2.1.1 Flat Wall SystemsWall Thickness: The nominal wall thickness of flat wallsystems is limited to 4 inches (102 mm), 6 inches (152 mm),8 inches (203 mm), or 10 inches (254 mm) in order toaccommodate systems currently available. Throughout theStandard, calculated design strength (capacity) is based onan actual thickness of 1⁄2-inch (13 mm) less than the specifiednominal thickness, and required strength (demand) is basedon the specified nominal thickness. For example, in deter-mining the length of solid wall required to resist seismicforces by Chapter 5 for a 6-inch (152 mm) nominal flat wall,the design strength of the wall is based on a thickness of 5.5inches (140 mm), whereas the required strength is based onthe mass (weight) of a 6-inch (152 mm) thick wall i.e., 75 psf(3.59 kN/m2) assuming a unit weight of concrete of 150 pcf(23.55 kN/m3). This approach was judged to provide anadequate margin of safety for all ranges of actual thick-nesses permitted by Table 2.1, Note 4, whether 1⁄2-inch(13 mm) less or 1⁄4-inch (6 mm) more than the statednominal thickness. Note 4 indicates that these tolerancesare applicable to the as-built wall so that it is clear thatadditional deviation from these plus and minus tolerancesin the field is not permitted.
C2.1.2 Waffle-Grid Wall SystemsCore Thickness and Width: Designs in this Standard thatare dependent upon the mechanical properties of the verticalcores (e.g., vertical wall steel in Chapter 4) are based on anequivalent rectangular or square cross-section determined asfollows. The core cross-sections of several waffle-grid formmanufacturers were evaluated and it was found that thevariation among the manufacturers was minimal. Next arepresentative cross-section was determined for eachnominal thickness. In the case of the 6-inch (152 mm)waffle-grid form, an ellipse was assumed with dimensions of
5.5 inches (140 mm) in thickness by 8 inches (203 mm) inwidth (see Figure 2.2). In the case of the 8-inch (203 mm)waffle-grid form, a circle was assumed with a diameter of 8inches (203 mm). Next an equivalent rectangle or square wasdetermined that resulted in the same moment of inertia, I, asthe ellipse or circle. For the 6-inch (152 mm) waffle-grid, theequivalent rectangle had dimensions of 5 inches (127 mm) inthickness and 6.25 inches (159 mm) in width. For the 8-inch(203 mm) waffle-grid, the equivalent rectangle was a squarewith each side being 7 inches (178 mm). Notes 5 and 6 ofTable 2.1 permits core cross-sections of other shapesprovided the moment of inertia, I, is the same. Minimumthickness and area limitations are also imposed on the alter-nate shape to assure that the section modulus and out-ofplane shear area, respectively, are not less than that of theequivalent rectangle or square.
Core Spacing: The vertical and horizontal core spacing islimited per Table 2.1 in order to accommodate the waffle-grid wall systems currently available. Variation in the waffle-grid forms available is minimal.
Web Thickness: The minimum web thickness of 2 inches(51 mm) is based on waffle-grid systems currently available.Variation in the waffle-grid forms available is minimal; there-fore, the tables in the Standard should produce economicaldesigns for buildings meeting the applicability limits ofSection 1.2 and Table 1.1.
Maximum Weight: The horizontal and vertical coresystems of the various form manufacturers vary; therefore,the weight per unit area of wall indicated in Table 2.1 isbased on the upper bound limit of the forms in use at thetime the original provisions were developed. The designs inthis Standard are based on these unit weights. For seismicdesign, the mass (weight) of the concrete walls in thebuilding represents the bulk of the total mass of thebuilding. Consequently where seismic design is required, it isimportant that the weight of the wall be approximately thesame as assumed in the design or less. For this reason, Table2.1, Note 3, establishes a maximum tolerance of 6 percenton any increased weight above that specified in the table.This allowable increase is consistent with Note 4 of the tablewhich permits a 4-inch (102 mm) nominal flat wall to beconstructed up to one-quarter inch (6 mm) thicker than thespecified nominal thickness.
C2.1.3 Screen-Grid Wall Systems
Core Thickness and Width: Designs in this Standard thatare dependent upon the mechanical properties of the vertical
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Appendix C – Commentaries
cores (e.g., vertical wall steel in Chapter 4) are based on anequivalent square cross-section determined as follows. Thecore cross-sections of several screen-grid form manufacturerswere evaluated and it was found that the variation amongthe manufacturers was minimal. Next a representative cross-section was determined. For the 6-inch (152 mm) screen-gridform a circle was used with a diameter of 6.25 inches (159mm). Next an equivalent square was determined that re-sulted in the same moment of inertia, I, as the circle. For the6-inch screen-grid the equivalent square had 5.5-inch (140mm) sides. Note 7 of Table 2.1 permits core cross-sections ofother shapes provided the moment of inertia, I, is the same.Minimum thickness and area limitations are also imposed onthe alternate shape to assure that the section modulus andout-of-plane shear area, respectively, are not less than that ofthe equivalent square.
Core Spacing: The vertical and horizontal core spacing islimited per Table 2.1 in order to accommodate most of thescreen-grid wall systems currently available.
Maximum Weight: The horizontal and vertical coresystems of the various form manufacturers vary; therefore,the weight per unit area of wall indicated in Table 2.1 isbased on the upper bound limit of the forms in use at thetime the original provisions were developed. The designs inthis Standard are based on these unit weights. For seismicdesign, the mass (weight) of the concrete walls in thebuilding represent the bulk of the total mass of the building.Consequently where seismic design is required, it is impor-tant that the weight of the wall be approximately the sameas assumed in the design or less. For this reason, Table 2.1,Note 3, establishes a maximum tolerance of 6 percent onany increased weight above that specified in the table. Thisallowable increase is consistent with Note 4 of the tablewhich permits a 4-inch (102 mm) nominal flat wall to beconstructed up to 1⁄4-inch (6 mm) thicker than the specifiednominal thickness.
C2.2 CONCRETE
C2.2.3 Maximum Aggregate Size
The maximum aggregate size is based on requirements inACI 318 [C2.1]. These limitations on aggregate size areintended to result in concrete that can be placed such that itproperly encases reinforcement and minimizes honeycombingand voids. The exception, which is also based on ACI 318, islimited to use with removable forms because proper place-
ment and encasement of reinforcement can be verifiedthrough visual inspection after removal of forms.
Concrete for walls less than 8 inches (203 mm) thick is typi-cally placed in the forms by using a 2-inch- (51-mm-) to 4-inch- (102-mm-) diameter boom or line pump; aggregatelarger than 3⁄4-inch (19 mm) may clog the line.
C2.2.4 Proportioning and Slump of Concrete
The maximum slump requirements are based on currentpractice. Considerations included in the prescribed maximumsare ease of placement, ability to fill cavities thoroughly, andlimiting the pressures exerted on the form by fresh concrete.
Where removable wall forms are used, the recommendedmaximum slump of concrete is 6 inches (152 mm). Themaximum slump is based on experience with ease of place-ment, ability to fill cavities thoroughly, and limiting the pres-sures exerted on the form by fresh concrete. The 6-inch(152 mm) maximum slump refers to the characteristics of thespecified mixture proportions based on water/cementitiousmaterials ratio only. The exception envisions the use of mid-range or high-range water-reducing admixtures to increasethe slump above 6 inches (152 mm), since their use does notadversely affect the tendency of the aggregate to segregate.
The minimum slump requirement for walls cast in stay-in-place forms is based on the PCA report, “Concrete Consoli-dation and the Potential for Voids in ICF Walls” [C2.2]. It isimportant that the concrete mix design utilize proper mate-rials in the proper proportions so that the specified strengthis achieved at the specified slump (i.e., greater than 6 inches[152 mm]). Ordering a concrete mix at a lower slump (e.g.,4 inches [102 mm]) and adding water at the job site toincrease the slump to more than 6 inches (152 mm) willadversely affect the strength of the concrete, and possiblyjeopardize the safety of the structure. Normally it would beexpected that a concrete mixture with a specified slump inexcess of 6 inches (152 mm) would contain mid-range orhigh-range water-reducing admixtures so as to mitigate thepossibility of segregation of the aggregate.
Self-consolidating concrete (SCC) mixtures are so fluid, astandard slump test (ASTM C143) does not yield meaningfulresults. Instead of measuring the “slump” of SCC, the diam-eter of the pile of concrete or “slump flow” is determined inaccordance with ASTM C1611 [C2.3]. The slump flow isdetermined by filling a standard ASTM C143 slump conewith concrete, removing the cone, and measuring the diam-eter of the pile of concrete. In the study referenced in Section
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C2.2.6, the initial slump flow of the SCC was 22 inches(559 mm).
C2.2.5 Compressive Strength
The minimum specified compressive strength of concrete of2,500 psi (17.2 MPa) is based on the minimum current prac-tice, which corresponds to minimum compressive strengthpermitted by ACI 318 [C2.1] and most building codes. TheStandard provides adjustment factors in the footnotes oftables that recognize the benefits of using higher strengthconcrete. For all buildings assigned to Seismic DesignCategory D0, D1 or D2, a minimum specified compressivestrength of concrete of 3,000 psi (20.7 MPa) is requiredwhich is consistent with Chapter 21 of ACI 318 [C2.1].
C2.2.6 Consolidation of Concrete
The requirement to internally vibrate concrete placed in stay-in-place forms is based on the PCA report, “Concrete Con-solidation and the Potential for Voids in ICF Walls” [C2.2].The report provided information on concrete within a varietyof stay-in-place form systems, placed using different meansof consolidation. Three mix designs were used in the study.A standard mix design with a slump between 4 inches(102 mm) and 8 inches (203 mm) showed that internalvibration is required. Two of the mixtures were intended tobe used without internal vibration and good results wereobtained with both. One mixture utilized a high-range water-reducing admixture to achieve a slump between 8 inches(203 mm) and 10 inches (254 mm). The other containeda high-range water-reducing admixture and a viscosity-modi-fying admixture to achieve a self-consolidating concrete (SCC)with a slump in excess of 8 inches (203 mm). Slumps inexcess of 8 inches (203 mm) should not be obtained by theuse of water alone since segregation is likely.
C2.3.1 Steel Reinforcement
The types of steel reinforcement permitted by the Standardare consistent with ACI 318 [C2.1]. Type R is specified forASTM A996 (rail steel) because the ASTM standard permitstwo designations. The type designated R is specified becauseit is the only one of the two that complies with the morestringent bend requirements of ACI 318. ASTM A615Grade 60 (420 MPa) reinforcing steel that complies with theadditional criteria of Section 21.2.5 of ACI 318, or ASTMA706 (low-alloy) Grade 60 (420 MPa) reinforcing steel isrequired in all buildings assigned to Seismic Design CategoryD0, D1 or D2 for improved ductility. This too is consistentwith ACI 318.
C2.3.2 Anchor Bolts
All bolts in the prescriptive details of Figures 6.3 through6.14 may be subject to tensile loading. Since the concretebreakout strength in tension is considerably greater for aheaded bolt versus a hooked bolt of the same size andembedment depth, the prescriptive designs are based onthe use of bolt with heads. In lieu of bolts with heads, theprovisions permit the use of rods with threads on both endswith the end embedded in the concrete having a hex orsquare nut. The provisions require that bolts complying withASTM F1554 be Grade 36 where used in multiple dwellingsassigned to Seismic Design Category C, and all in buildingsassigned to Seismic Design Category D0, D1 or D2 becauseACI 318 [C2.1] requires that connections subjected to seismicforces be designed to fail in a ductile manner. Therefore, it isimperative that bolts with a higher yield strength or boltslarger than specified in the figures not be used in these con-nections since it is likely that in the event of a load beingapplied that is greater than that assumed in design, theconcrete may fail prior to the bolt yielding.
C2.3.3 Miscellaneous Steel Items
Grade 33 is the minimum grade of sheet steel specified forcomponents of connections in Figures 6.3 through 6.14because it is the lowest strength recognized under thestandards for “structural steel” (Type SS). The requirementapplies to angles and other components of connectionsthat are field fabricated and is not intended to apply toproprietary clip angles and other proprietary connectorsthat are available.
C2.4 FORMMATERIALS ANDFORM TIESThe materials listed are based on currently availableremovable and stay-in-place forming systems. From a struc-tural design standpoint, the material can be anything thathas sufficient strength and durability to contain the concreteduring pouring and curing. From a building science stand-point, materials that stay-in-place after concrete cures mustbe able to withstand the rigors of the environment. From athermal standpoint, most stay-in-place form systems andsome removable form systems that incorporate insulationinto the wall before the concrete is placed, provide enoughinsulating value to meet local building code requirements.However, some forming systems will require the addition ofinsulation to the interior or exterior of the concrete wall tomeet code requirements for insulating value. From a life-safety standpoint, the form material can be anything that
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meets the criteria for flame-spread and smoke development.This section is not intended to exclude the use of existing orfuture materials provided that the requirements of theStandard are met.
C2.5.7. Alternate Grade of Reinforcement andSpacing
The following example illustrates the use of Table 2.3. FromTable 4.1, Minimum Vertical Reinforcement for Flat Above-Grade Walls, for a 6-inch (152 mm) nominal flat wall that is10-feet (3.0 m) high with the floor load transferred to thewall by a ledger (side bearing), located where the basic windspeed is 150 mph (241 km/hr), Exposure C, the table speci-fies No. 5 bars at a maximum spacing of 31 inches (787 mm)on center. The bar size and spacing specified in Table 4.1 arebased on Grade 60 (420 MPa) reinforcement; however, thecontractor prefers to use Grade 40 (280 MPa), No. 4 bars.What is the maximum spacing permitted for Grade 40 (280MPa), No. 4 bars that will provide an area of steel equal tothat provided by Grade 60 (420 MPa), No. 5 bars spaced at31 inches (787 mm) on center?
Step 1. At the top of Table 2.3 under the heading “Bar sizefrom applicable table in Chapter 3 or Chapter 4” find thegroup of columns that is applicable to the bar size deter-mined from Table 4.1. In this example, this is the group ofcolumns for a No. 5 bar.
Step 2. Under the portion of the table for No. 5 bars, andunder the heading “Alternate bar size and/or alternate gradeof steel desired to be used” locate the group of columns forGrade 40 (280 MPa), which is the Grade of steel thecontractor wishes to use.
Step 3. Within the group of columns for Grade 40 (280MPa) reinforcement, locate the column that applies to the barsize the contractor wishes to use which in this case is No. 4.
Step 4. Go down this column until reaching the cell in therow that corresponds to 31 inches (787 mm) in the left-mostcolumn (with the heading “Bar Spacing From ApplicableTable in Chapter 3 or 4”) and read 13 inches (330 mm) whichis maximum spacing permitted if Grade 40 (280 MPa), No. 4bars are used in lieu of Grade 60 (420 MPa), No. 5 bars.
C2.7 COVERING FOR STAY-IN-PLACEFORMS
C2.7.1 Interior Covering
The requirements for covering foam plastic that would other-wise be exposed to the interior of the building are based oncurrent building codes and are self-explanatory. Adhesivelyattaching the gypsum board to the foam plastic as the onlymeans of fastening is not permitted out of concern thatwhen the adhesive is exposed to higher temperature expectedin a fire, it may soften and allow the gypsum board todelaminate from the foam plastic.
C2.7.2 Exterior Wall Covering
It is generally accepted that a monolithic concrete wall is asolid wall through which water and air cannot readily flow;however, there is a possibility that the concrete wall mayhave drying shrinkage cracks through which water mayenter. Small gaps between stay-in-place form blocks areinherent in current screen-grid stay-in-place form walls andmay allow water to enter the structure. As a result, a mois-ture barrier on the exterior face of the stay-in-place formwall is generally required and should be considered minimumacceptable practice.
REFERENCES
C2.1 Building Code Requirements for Structural Concrete(ACI 318-05) and Commentary (ACI 318R-05).American Concrete Institute, Farmington Hills,Michigan. 2004.
C2.2 Gajda, J., and Dowell, A. M., Concrete Consolidationand the Potential for Voids in ICF Walls, RD134,Portland Cement Association, Skokie, Illinois, 2003.
C2.3 ASTM C1611/C1611M-05, Standard Test Method forSlump Flow of Self-Consolidating Concrete. AmericanSociety for Testing and Materials (ASTM), WestConshohocken, Pennsylvania. 2005.
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CHAPTER 3 COMMENTARY –FOOTINGS AND FOUNDATIONWALLS
C3.1 FOOTINGS
C3.1.1 General
Footing requirements are based on conventional concreteconstruction; however, the Standard provides a table forminimum footing widths for flat, waffle-grid, and screen-gridwalls. Stay-in-place forms for footings are currently availableand may be used if they meet the minimum footing dimen-sions required in Table 3.1.
C3.1.2 Minimum Footing Size
The minimum footing width values are based on two buildingwidths; 32 feet (9.8 m) and 40 feet (12.2 m). Two floor spansare shown; 20 feet (6.1 m) and 32 feet (9.8 m). A roof over-hang with a horizontal projection of 2 feet (610 mm) wasincluded on all sides of the building. The table has footingwidths for two ground snow load conditions; 30 psf (1.44kN/m2) and 70 psf (3.35 kN/m2). The ground snow loadswere converted to roof snow loads in accordance with ASCE7 [C3.2]. This conversion resulted in a roof snow load that is77% of the ground snow load. Minimum footing widths arebased on the maximum dead and live loading conditionsfound in Table 1.1. The widths assume a minimum footingdepth of 12 inches (305 mm) below grade, and the assump-tion that walls in all stories are constructed with concrete,and unless otherwise noted, are the same thickness.
The dead load of concrete walls is based on the weights perunit area given in Table 2.1. Where two or more wall typesare grouped, the largest value of all the grouped wall typeswas used. The values in Table 2.1 do not include any interiorand exterior wall finishes that may be applied to the wall;therefore, 2 psf (0.10 kN/m2) and 11 psf (0.53 kN/m2) wereincluded to account for interior and exterior finishes, respec-tively. The allowance for the exterior finish on the basementwall was reduced to 3 psf (0.14 kN/m2). The 2 psf (0.10kN/m2) value used for the interior wall finish should beadequate for interior finishes typically used, including a 1⁄2-inch (13 mm) gypsum wallboard thermal barrier which isusually required over foam plastic. The 11 psf (0.53 kN/m2)value included for the exterior finish should be adequate formost weather resisting coverings, including 7⁄8-inch (22 mm)of cement plaster stucco. Additional footing widths aregiving for masonry veneer having an installed weight of 40psf (1.92 kN/m2). The masonry veneer is assumed to be
supported by the footing; therefore, the additional weight isalso included for the basement wall.
Heights of concrete walls were assumed as follows:basement wall 10 feet (3 m) from top of footing to top offirst floor, first story wall 10 feet (3 m) from top of floor totop of floor in second story, and second story wall 8 feet(2.4 m) from top of floor to top of wall. For a one-storyhouse, the first story wall was assumed to be 9 feet (2.7 m)from the top of the first floor to top of the wall. Theseassumptions result in walls that are theoretically 4 feet(1.2 m) shorter than would be permitted for a two-storyhouse (assuming a floor assembly depth of one-foot (305mm)), and 2 feet (610 mm) shorter for a one-story house.While these heights are slightly less than would be permittedif each story had the maximum allowable unsupported wallheight of 10 feet (3 m) permitted elsewhere in the Standard,it was felt that since all other conditions were based onmaximum conditions, which will probably never occur in anactual home, and given the conservatism in establishing theallowable load-bearing value of the soil, the reductions arereasonable. It was assumed that walls in the first and secondstory have 15% openings, and the basement walls have 5%openings. This was done to recognize that openings reducethe dead load of the wall.
The values in Table 3.1 for a one-story structure account fora concrete wall one story above-grade. The values in thetable for a two-story structure account for a concrete walltwo stories above-grade. The values in the table account fora basement wall in all cases. Table note 5 permits the footingwidth to be reduced if specific conditions exist where there isno basement.
The load used to size the footing was based on the moststringent determined from the following three allowablestress design load combinations from ASCE 7 [C3.2].
D + L
D + S
D + 0.75(L + S)
Where D = dead load
L = live load, and
S = roof snow load
Footnote 1 to Table 3.1 provides guidance for sizing thethickness of an unreinforced footing based on a rule ofthumb. This requirement is generally conservative and may
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be relaxed when a registered design professional designs thefooting. Soil borings are rarely required for residentialconstruction except where there are known risks or a historyof problems (i.e., organic deposits, landfills, expansive soils)associated with building in certain areas. For an approximaterelationship between soil type and presumptive (orallowable) load-bearing value, refer to the applicablebuilding code.
C3.2 FOUNDATIONWALLREQUIREMENTS – GENERALThe Standard provides reinforcement tables for foundationwalls constructed within the applicability limits of Section 1.2and Table 1.1. The maximum design conditions are SeismicDesign Category D2, ground snow load of 70 psf (3.35kN/m2), and design lateral soil load of 60 psf/foot (9.43kN/m2/m) of depth. The Standard provides the minimumrequired vertical and horizontal wall reinforcement forvarious lateral soil loads, wall heights, and unbalanced back-fill heights. Vertical wall reinforcement tables are providedfor foundation walls with unsupported wall heights up to10 feet (3 m).
Residential construction makes widespread use of walls thatprovide 8-foot (2.4 m) ceiling heights; however, homes areoften constructed with higher ceilings. Walls are groupedinto three categories as follows:
1. walls with soil backfill having a maximum design lateralsoil load of 30 psf/ft (4.71 kN/m2/m) of depth;
2. walls with soil backfill having a maximum design lateralsoil load of 45 psf/ft (7.07 kN/m2/m) of depth; and
3. walls with soil backfill having a maximum design lateralsoil load of 60 psf/ft (9.43 kN/m2/m) of depth.
Walls were designed in accordance with ACI 318 [C3.1].The following design assumptions were used to analyzethe walls:
1. Walls are simply supported at the top and bottom ofeach story.
2. Walls contain no openings.
3. Lateral bracing is provided for the wall by the floorsabove and floor slabs below.
4. Allowable deflection criterion is the laterally unsupportedheight of the wall, in inches, divided by 240.
The load combination used to design foundation walls was:
U = 1.2D + 1.6(L + H) + 0.5S
For concrete walls subjected to lateral soil loads, H, and lowgravity loads D, L and S (dead, live and snow, respectively),it is conservative to ignore the gravity loads. Consequently,foundation walls in the tables in this section were designedfor:
U = 1.6H
Although in some cases a wood ledger board or cold-formedsteel track will be bolted to the inside face of the foundationwall at the top to support floor construction, the momentinduced in the wall due to this eccentric load was ignoredbecause it reduces the moment induced by the lateralsoil load.
For flat walls, design strength (i.e., capacity) and sectionproperties were based on thicknesses of 3.5, 5.5, 7.5 and9.5 inches (89, 140, 191 and 241 mm). This approach willprovide adequate strength regardless of whether the formsused are 1⁄2-inch (13 mm) less than the stated nominal thick-ness of 4, 6, 8 or 10 inches (102, 152, 203 or 254 mm), or1⁄4 -inch (6 mm) more than the stated nominal thickness.
Design strength and section properties for waffle- andscreen-grid walls were based on concrete sections as follows.For 6-inch (152 mm) and 8-inch (203 mm) waffle-grid walls,rectangular cross-sections with through-the-wall thicknessesof 5 inches (127 mm) and 7 inches (178 mm), respectively,were used. The lengths of the rectangles for 6-inch (152mm) and 8-inch (203 mm) walls were 6.25 (159 mm) and7 inches (178 mm), respectively. For 6-inch (15 mm) screen-grid walls, a square cross-section with 5.5-inch (140 mm)sides was used. The spacing of the rectangular resistingelements was 12 inches (305 mm) since this is the maximumspacing of vertical cores permitted by Table 2.1. In the caseof waffle-grid walls, the web was ignored for computingsection properties and resisting out-of-plane shear.
Deflection limits are primarily established with regard toserviceability concerns. The intent is to prevent excessivedeflection, which may result in cracking of finishes. For walls,most codes generally agree that L/240 represents an accept-able serviceability limit for deflection. For walls with flexiblefinishes, less stringent deflection limits may be used. In caseswhere the calculations required no vertical wall reinforce-ment for 5.5-inch (140 mm) flat and 6-inch (152 mm)waffle-grid walls cast in stay-in-place forms, a minimum wallreinforcement of one vertical No. 4 bar at 48 inches (1219mm) on center is a recommended practice to account forpotential honeycombing, or construction errors that may notbe evident since the forms remain in place.
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Minimum horizontal wall reinforcement is based on recom-mendations in Design Criteria for Insulating Concrete FormWall Systems [C3.3]. The minimum reinforcement allows fortemperature, shrinkage, potential honeycombing, voids, orconstruction errors.
Some Insulating Concrete Form manufacturers make specialforms that permit a corbel or projection for the support ofmasonry veneer to be cast into the face of the outside of afoundation wall. Since the load on the corbel is offset fromthe centerline of the wall, it induces a moment in the wallthat is additive to the moment due to the lateral soil load.Since the tables in this chapter do not take this additionalmoment into consideration, walls incorporating corbels arenot within the scope of the prescriptive tables in this chapter.
It is common practice to reduce the thickness of foundationwalls approximately 4 inches (102 mm) to form a shelf forthe support of masonry veneer. Generally the shelf is notlocated at the floor assembly that provides lateral support forthe top of the foundation wall. The provisions permit thevertical reinforcement for the foundation wall to be based onthe thicker portion of the wall provided the shelf is locatednot more than 24 inches (610 mm) below the underside ofthe floor assembly and the reduction in thickness does notexceed 4 inches (104 mm). This assures that the location ofthe reduction in thickness is not near the point of maximummoment, which for a foundation wall is generally in thelower one-half of the wall height.
C3.2.1 Stem Walls with Slab-on-Ground
Stem wall thickness and height are determined as thosewhich can distribute the building loads safely to the earth.The stem wall thickness should be equal to or greater thanthe thickness of the above-grade wall it supports. Given thatstem walls are relatively short and are backfilled on bothsides, lateral earth loads induce a small bending moment inthe walls; accordingly, lateral bracing should not be requiredbefore backfilling.
C3.2.1.2 StemWalls Laterally Supported at Top
The required tributary weights in Table 3.2 were determinedas follows. The stem wall was considered to be pinned at thefinished ground level on the outside of the wall and laterallysupported by the earth. The top of the first story wall wasconsidered to be pinned and laterally supported by the flooror roof construction at that level. The top of the stem walland bottom of the first story wall were each considered tobe pinned at the top of the slab-on-ground and laterallysupported by the slab-on-ground. The first story wall was
subjected to the design wind pressure (combined suction onthe outside and positive internal pressure on the inside) asexplained in Section C4.1. In addition, the first story wall wasassumed to be supporting the floor of a second story by awood ledger or cold-formed steel track attached to the sideof the wall (see Section C4.1). Attachment of a floor to theside of the wall is more severe than where a floor or roof issupported on top of the wall since the eccentric loadsubjects the wall to additional moment which increases thehorizontal reaction at the slab-on-ground. These individualloads were combined in accordance with the strength designload combinations of ASCE 7 [C3.2] to determine thehorizontal reaction at the bottom of the first story wall at theslab-on-ground. It should be noted that the eccentricity ofthe second story floor load was based on a 10-inch (254mm) nominal wall having a stay-in-place form with athickness of 21⁄2 inches (64 mm). A parametric study showedthat the reduction in the reaction at the bottom of the wallfor a thinner wall is very small; therefore, no provision forreducing the required tributary weight (i.e., reaction) of Table3.2 for thinner walls is provided. The portion of the stemwall between the top of the slab-on-ground and finishedground level was subjected to the design wind pressure(suction on the outside only), the lateral soil load due to thebackfill beneath the slab-on-ground, and a surcharge loadequal to the design live load on the floor. Utilizing theseforces, the horizontal reaction at the top of the stem wall(i.e., top of the slab-on-ground) was determined. Thehorizontal reactions at the top of the stem wall and thebottom of the first story wall were summed to determine therequired tributary weights given in Table 3.2.
The stem wall was subjected to the design wind pressure(suction on the outside only), and the force due to the lateralsoil load of the backfill beneath the slab-on-ground. In addi-tion, a surcharge live load of 40 psf (1.92 kN/m2) was placedon the slab-on-ground. The surcharge load was converted toa uniform lateral load by multiplying by the coefficient ofearth pressure, K, implied by the lateral soil loads used in thedesign of the stem wall (i.e., 30, 45 and 60 psf/ft (4.71, 7.07and 9.43 kN/m2/m) of depth). Lateral soil load is the productof K and the density of the soil; therefore, by assuming a soildensity of 110 pcf (17.27 kN/m3), a value of K was com-puted for each soil class. For example, the value of K for soilthat produces a lateral soil load of 60 psf/ft (9.43 kN/m2/m)is 0.55 (60/110 = 0.55). These individual loads were com-bined in accordance with the strength design load combin-ations of ASCE 7 [C3.2] to arrive at the horizontal reaction atthe top of the stem wall at the slab-on-gound.
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The horizontal reactions at the slab-on-ground for theabove-grade (first story) wall and stem wall were summedand presented in Table 3.2 as the “required [factored] tribu-tary weight of slab-on-ground for anchorage of stem wall.”Since the tabulated values are based on the assumption thatthe first story wall supports a floor at the top attached to theside of the wall, a table note permits a reduction where theload supported by the wall bears on the top of the wall.
To provide resistance to the outward-acting forces on thestem wall and first story wall at the slab-on-ground, the wallmust be anchored to the slab. Since there may be insufficientthickness in some thinner walls to fully develop a hooked barin the wall, the minimum nominal wall thickness is limited to6 inches (152 mm) and the anchor bar is required to engagea horizontal bar in the wall. In addition, the maximumanchor spacings of 48 inches (1219 mm) and 27 inches(686 mm) are intended to keep the tensile force in the barto less than one-half the design tensile strength of the bar.A Grade 40 (280 MPa) No. 4 bar has a design tensilestrength of 7,200 pounds (0.9*0.20*40,000 = 7,200)(32.0 kN). The largest required tributary weight in Table 3.2is approximately 1,550 plf (22.6 kN/m); therefore, the tensileforce in a No. 4 bar spaced at 27 inches (686 mm) is 3,488pounds (1550*(27/12) = 3,488) (15.5 kN) which is slightlyless than one-half the design tensile strength of the bar(i.e., 3488/7200 = 0.48).
Although the wall may be anchored to the slab, this doesnot assure that it will not move when the design forces acton it. Therefore, the weight of the slab attached to the wallmust be equal to or greater than the outward-acting forceon the wall. Table 3.3 gives the factored weights provided byslabs of different thicknesses and different lengths perpen-dicular to the wall. The factored weight, W, provided by agiven length, L, and thickness, t, of slab was calculated asfollows:
W = 0.9*L*(t/12)*150*0.70
The constant 0.9 is the load factor for dead load, 150 (23.55kN/m3) is the weight of one cubic foot of concrete, and 0.70is the coefficient of friction between the slab and a polyeth-ylene vapor retarder. Since most building codes require avapor retarder to be placed beneath a concrete slab-on-ground, it is assumed that the slab will be cast on a vaporretarder. Research has shown that the coefficient of frictionat which a slab on a polyethylene sheet will first move is 0.70,which then drops to 0.50 for average subsequent movement.In view of the high load factor of 1.6 on wind loads andlateral soil loads, the higher value of 0.70 was used.
Because of the possibility of drying shrinkage cracks, or thepresence of contraction (control) joints or construction joints,or both, reinforcement is required to assure that the slabcounted on to resist the reaction remains intact to act as aunit. The weight of slab that a given area of steel reinforce-ment, As, of yield strength, fy, can prevent from being drugover the subgrade is the same as the design tensile strengthof the steel which is:
W = 0.9*As*fy
The constant 0.9 is the strength reduction factor.
C3.2.2 Crawlspace Walls
Table 3.4 applies to crawlspace walls 5 feet (1.5 m) or less inheight with a maximum unbalanced backfill height of 4 feet(1.2 m). Loading conditions were as described previously inSection C3.2. The values for minimum vertical wall reinforce-ment are based on the controlling loading condition.
Soil borings are rarely required for residential constructionexcept where there are known risks or a history of problems(i.e., organic deposits, landfills, expansive soils) associatedwith building in certain areas. Refer to the applicable build-ing code or ASCE 7 [C3.2] for an approximate relationshipbetween soil classifications and design lateral soil loads.
Backfilling should not occur without lateral support at thetop of the wall from either the first floor structure or tempo-rary bracing unless the backfill height is less than 4 feet (1.2m). This requirement ensures that the backfill does not causethe wall to overturn. Concrete walls can withstand thehigher lateral load created from the backfill when the top ofthe wall is braced and axial loads are present on the wall.Typically, providing lateral bracing at the top of the wall untilthe structure above is in place is sufficient.
C3.2.3 Basement WallsTables 3.5 through 3.12 apply to basement walls. Loadingconditions were based on lightest possible gravity loadsexperienced in residential construction (i.e., a zero dead loadas described previously). The values for minimum vertical wallreinforcement are based on the controlling loadingcondition. Design lateral soil loads are based on moist soilconditions without hydrostatic pressure.
Soil borings are rarely required for residential constructionexcept where there are known risks or a history of problems(i.e., organic deposits, landfills, expansive soils) associatedwith building in certain areas. Refer to the applicablebuilding code or ASCE 7 [C3.2] for an approximate relation-ship between soil classifications and design lateral soil loads.
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Backfilling should not occur without lateral support at thetop of the wall from either the first floor structure or tempo-rary bracing unless the unbalanced backfill height is less thanone-half the basement wall height. This requirement ensuresthat the backfill does not cause the wall to overturn.Concrete walls can withstand the higher lateral loads createdfrom the backfill when the top of the wall is braced and axialloads are present on the wall. Typically, providing lateralbracing at the top of the wall until the structure above is inplace is sufficient.
C3.3 LOCATIONOF REINFORCEMENTINWALLThe amount of reinforcement required by Table 3.4 andTables 3.6 through 3.11 for a given condition of wall type,height, backfill height, and design lateral soil load wascomputed based on the centroid of the vertical reinforce-ment being at the center of the wall. In engineering terms,the effective depth, d, was one-half the wall thickness. Thepredecessor to this Standard required the reinforcement tobe located within the center one-third of the wall thickness.Depending upon how this was interpreted, this allowed thecentroid of the vertical reinforcement to vary by up to one-sixth the wall thickness from the location assumed in thecalculations. This meant that the effective depth for a 6-inch(152 mm) wall was reduced one inch (25.4 mm) if the rein-forcement was positioned toward the outside (the flexuralcompression side) of a basement wall. This amounted to areduction in d of approximately 33%. Since the designmoment strength is approximately proportional to the effec-tive depth, this misplacement of the reinforcement fromwhere it was assumed in the design resulted in an approxi-mately 33% reduction in design moment strength. Inaddition, by placing the reinforcement closer to the compres-sion face of the wall, there is increased risk that should thewall be subjected to more lateral load than was assumed indesign, it may fail by compression of the concrete ratherthan yielding of the steel.
Table 3-12 is based on the vertical reinforcement beingplaced with a cover of 1.25 inches (32 mm) from the insideface of the wall. This greatly increases the effective depth,d, for the thicker walls recognized in this Standard, thussignificantly increasing the moment strength for a givenamount of reinforcement. Use of Table 3-12 is restricted tosituations where there are 4 feet (1.2 m) or more ofunbalanced backfill to assure that moment-reversal causedby outward acting wind pressure does not control.
This Standard requires that the vertical reinforcement beplaced within a tolerance of the larger of 10% of the wallthickness and 3⁄8-inch (10 mm). The latter criterion is basedon the tolerance on d in ACI 318 [C3.1] for members witheffective depth, d, less than or equal to 8 inches (203 mm).Since this Standard has provisions for 31⁄2-inch walls (89 mm),the ACI 318 [C3.1] tolerance of 3⁄8-inch (10 mm) is approxi-mately 10% of the wall thickness. Based on this, it wasdecided that if 10% tolerance was permitted for a very thinwall, then it should also be acceptable for thicker walls.
C3.4 EXTERIOR FOUNDATIONWALLCOVERINGSIt is generally accepted that a monolithic concrete wall is asolid wall through which water and air cannot readily flow;however, there is a possibility that the concrete wall mayhave honeycombs, voids, or hairline cracks through whichwater may enter. Small gaps between blocks are inherent incurrent screen-grid stay-in-place form walls and will allowground water to enter the structure. As a result, a moisturebarrier on the exterior face of all below-grade walls is gener-ally required and should be considered good practice. Due tothe variety of materials on the market, waterpproofing anddampproofing materials are typically specified by the manu-facturer. Petroleum-based dampproofing materials shouldnot be used with forms incorporating rigid foam plastic sincethe two materials are not compatible.
C3.5 TERMITE PROTECTIONREQUIREMENTSTermites need wood (cellulose) and moisture to survive. Rigidfoam plastic provides termites with no nutrition but canprovide access to the wood structural elements. Recently,some building codes have prohibited rigid foam plastics fornear- or below-grade use in heavy termite infestation areas.Code officials and pest control operators fear that foaminsulation provides a “hidden pathway.” Applicable buildingcode requirements, a local pest control company, and theform manufacturer should be consulted regarding this con-cern to determine if additional protection is necessary. Abrief list of some possible termite control measures follow.
1. Rely on soil treatment as a primary defense againsttermites. Periodic retreatment and inspection should becarried out by the homeowner or termite treatmentcompany.
2. Install termite shields.
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3. Provide a 6-inch (152-mm) high clearance above finishgrade around the perimeter of the structure where thefoam has been removed to allow visual detection of signsof termite activity.
4. The use of borate treated rigid foam plastic in forms astests show borate treated rigid foam plastic reducestunneling.
REFERENCESC3.1 Building Code Requirements for Structural Concrete
(ACI 318-05) and Commentary (ACI 318R-05).American Concrete Institute, Farmington Hills,Michigan. 2004.
C3.2 Minimum Design Loads for Buildings and OtherStructures, including Supplement No. 1, ASCE/SEI7-05. American Society of Civil Engineers, Reston,Virginia. 2005.
C3.3 Design Criteria for Insulating Concrete Form WallSystems, (RP 116). Prepared for the Portland CementAssociation by Construction Technology Laboratories,Inc., Skokie, Illinois. 1996.
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CHAPTER 4 COMMENTARY –ABOVE-GRADEWALLS
C4.1 ABOVE-GRADEWALLREQUIREMENTSThis Standard provides reinforcement tables for loadbearingand non-loadbearing above-grade walls constructed withinthe applicability limits of Section 1.2 and Table 1.1. The max-imum design condition is a basic wind speed of 150 mph(67 m/s), Exposure D, which results in a design wind pressureof 74.81 psf (3.58 kN/m2) for out-of-plane loads on walls(see table below). The Standard provides the minimumrequired vertical and horizontal wall reinforcement for dif-ferent design wind pressures and three wall heights. Verticalwall reinforcement tables are limited to one- and two-storybuildings for non-load bearing and load-bearing walls.
Residential construction makes widespread use of 8-foot(2.4 m) ceilings; however, homes are often constructed withhigher ceilings. Therefore, walls with laterally unsupportedheights up to 10 feet (3 m) are accommodated. Concretewalls are grouped into two categories as follows:
1. Gravity load transfer by construction bearing on the topof the wall and concentric with the centerline of thewall, designated “top” for top load bearing. This is typi-cally the situation for the top-story wall, or only story ofa one-story home.
2. Gravity load transfer from floor construction by woodledgers or cold-formed steel tracks bolted to the side ofa wall, designated “side” for side load bearing. This istypically the situation for the first story wall where thesecond floor assembly is supported by wood ledgers orcold-formed steel tracks attached to the side of the wall,and the second story wall is of concrete construction.The eccentricity assumed in this case was one-half thewall thickness plus 2.5 inches (64 mm) to allow for thethickness of stay-in-place form material such as foamplastic. Where floor framing members span parallel tothe wall, the gravity loads transferred to the wall are verylow; therefore, the “top” bearing condition can be usedin this situation.
The following design assumptions were used in analyzing thewalls for out-of-plane loads:
1. Walls are simply supported at each floor and roof thatprovides lateral support, or by the exterior finish groundlevel in the case where walls are continuous with stemwalls.
2. Lateral support is provided for the wall by the floors androof, and by the slab-on-ground where the wall is mono-lithic with or anchored to the slab.
3. Allowable deflection criterion is the laterally unsupportedheight of the wall, in inches, divided by 240.
4. The minimum possible axial load is considered for eachcase. For “top” bearing walls, no axial load was consid-ered. For “side” bearing walls, the moment induced bythe eccentricity of the dead and live load of the floorconstruction supported by the ledger board or cold-formed steel track bolted to the side of the wall wasconsidered since it is additive with the moment inducedby the outward-acting wind load. The axial load on thewall due to the floor construction supported by theledger board or cold-formed steel track was not consid-ered. Two strength load combinations of ACI 318 [C4.1]and ASCE 7 [C4.2] were checked:
U = 1.2D + 1.6L
U = 1.2D + 0.5L + 1.6W
where D is the dead load of floor construction (10 psf(0.48 kN/m2)) based on a 32-foot (9.8 m) span, L is thefloor live load (30 psf (1.44 kN/m2)) based on a 32-foot(9.8 m) span, and W is the outward-acting lateral loaddue to the wind pressure.
The seismic out-of-plane load, E, was also considered byreplacing 1.6W with 1.0E. After taking into the consider-ation the minimum reinforcement required by Section4.1.3 for buildings assigned to Seismic Design CategoryC or D, in all cases the load combination including windgoverned for above-grade walls that are not continuouswith stem walls. Where above-grade walls areconstructed continuous with stem walls, in some casesfor lower design wind pressures, seismic out-of-planeloads require a greater amount of reinforcement than theminimum required by Section 4.1.3 and for windpressure.
For above-grade walls constructed continuous with stemwalls (Table 4.4), the two load combinations shownabove also included the term 1.6H, where H is the lateralsoil load (i.e., 30 and 60 psf/ft (4.7 and 9.43 kN/m2/m) ofdepth). In addition, the floor live load, L, on the slab-on-ground (40 psf (1.92 kN/m2)) was included as a surchargeload. The surcharge load is the product of the floor liveload and the coefficient of earth pressure, K, implied bythe lateral soil load used in the design of the stem wall.Since lateral soil load is the product of K and the densityof the soil, by assuming a soil density of 110 pcf (17.27kN/m3), a value of K was computed for each soil class.
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For example, soil having a density of 110 pcf (17.27kN/m3) that has a design soil load of 60 pcf (9.42 kN/m2/m)has an implied K-value of 0.55 (60/110 = 0.55).
5. Wind loads were calculated in accordance with ASCE 7[C4.2] for enclosed buildings using components andcladding pressure coefficients for the wall interior zone(designated number 4 in Figure 6-11A of ASCE 7), effec-tive wind area of 10 sq. ft. (0.9 m2), and mean roofheight of 35 feet (10.7 m). For these conditions, theexternal pressure coefficient, GCp , is 1.1, and theinternal pressure coefficient, GCpi , is 0.18. The followingtable shows the design wind pressures for the variousbasic wind speeds and exposure categories and how theywere grouped for design purposes. The values in the
�s�h�a�d�e�d cells were used to design the walls within agroup. The basic wind speeds shown in the table in italicsrepresent the values required to produce a design windpressure for the various exposure categories that areequal to the value that is shaded. Although the highestbasic wind speed shown in Figure 6-1 of ASCE 7 for the50 states of the United States is 150 mph (67 m/s), 170mph (76 m/s) is listed in the figure to be used for Guam.
Computations to determine minimum steel reinforcementamounts in Tables 4.1, 4.2, 4.3, and 4.4 were performedusing the design wind pressures of ASCE 7 [C4.2] deter-mined above and the design provisions of ACI 318 [C4.1].Both of these standards were adopted by the 2006 IBC[C4.3]. In the case of Table 4.4, the design wind pressureacting as a suction on the portion of the wall above the slab-
on-ground were reduced for the stem wall portion of thewall by the ratio of the external pressure coefficient, GCp,and the sum of the external and internal pressure coefficients,GCp and GCpi, respectively, (1.10/(1.10 + 0.18) = 0.86), sinceno internal pressure is acting on that portion of the wall.
For flat walls, design strength (i.e., capacity) was based onthicknesses of 3.5, 5.5, 7.5 and 9.5 inches (89, 140, 191 and241 mm). This approach will provide adequate strengthregardless of whether the forms used are 1⁄2-inch (13 mm)less than the stated nominal thickness of 4, 6, 8 or 10 inches(102, 152, 203 or 254 mm), or 1⁄4-inch (6 mm) more thanthe stated nominal thickness.
For 6-inch (152 mm) and 8-inch (203 mm) waffle-grid walls,rectangular cross-sections with through-the-wall thicknessesof 5 inches (127) and 7 inches (178), respectively, were used.The lengths of the rectangles for 6-inch (152 mm) and 8-inch (203 mm) walls were 6.25 (159 mm) and 7 inches (178mm), respectively. For 6-inch (15 mm) screen-grid walls, asquare cross-section with 5.5-inch (140 mm) sides was used.The spacing of the rectangular resisting elements was 12inches (305 mm) in all cases since this is the maximumspacing of vertical cores permitted by Table 2.1. In the caseof waffle-grid walls, the web was ignored for computingsection properties and resisting out-of-plane shear.
Since factored gravity loads from construction concentricwith the centerline of the wall are very low when comparedto the product of the gross area of the wall, Ag, and specifiedcompressive strength of concrete, f'c (Ag f'c), they wereignored. P-delta effects were ignored because the loads aresmall and the deflection of the wall due to lateral loads isvery small (i.e., usually well under 1⁄8-inch (3 mm)). Momentmagnification was also ignored because the magnification isgenerally very small.
Deflection limits are primarily established with regard toserviceability concerns. The intent is to prevent excessivedeflection, which may result in cracking of finishes. For walls,most codes generally agree that L/240 represents an accept-able serviceability limit for deflection. For walls with flexiblefinishes, less stringent deflection limits may be used. Elasticdeflections for cracked sections were computed based onthe effective moment of inertia, Ie, as defined in Equation9-8 of ACI 318 [C4.1]. Computed deflections generally wereconsiderably less than 1⁄8-inch (3 mm); well below the L/240limitation which is 0.40-inch (10 mm) for an 8-foot (2.4 m)high wall.
Basic wind speed – mph Design wind pressure – psf
Exposure category Exposure category
B C D B C D
85 -14.73
90 -16.52
100 85 -20.39 -20.42
110 90 85 -24.67 -22.89 -24.02
120 100 90 -29.36 -28.26 -26.93
130 110 100 -34.46 -34.20 -33.25
140 120 110 -39.97 -40.70 -40.23
150 130 120 -45.88 -47.76 -47.88
166 140 130 -55.39 -56.19
179 150 140 -63.59 -65.17
192 163 150 -74.81
For SI: 1 mph = 0.4470 m/s; 1 psf = 0.0479 kN/m2
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In many instances, especially for lower lateral loads and/orfor thicker walls, a plain concrete wall has adequate momentstrength; however, it was decided to require a minimum ofone vertical No. 4 bar at 48 inches (1219 mm) on center forall above-grade wall applications. This requirement providesfor crack control, continuity, and a positive load path whereconcrete consolidation cannot be verified, such as wherestay-in-place forms are used. In addition, structural testingwas conducted at the NAHB Research Center, Inc. to deter-mine the in-plane shear resistance of concrete walls cast inICFs [C4.4]. All test specimens had one No. 4 vertical bar at48 inches (1219 mm) on center.
Based on recommendations in Design Criteria for InsulatingConcrete Form Wall Systems [C4.4], the minimum horizontalwall reinforcement is intended to limit crack widths thatcan occur due to temperature and shrinkage stresses, orconstruction errors.
The requirements for minimum reinforcement in walls ofSection 14.3 of ACI 318 [C4.1] have been waived in thisstandard for above-grade walls in accordance with Section14.2.7 of ACI 318 based on adequate strength and stabilitydemonstrated both by calculation of capacity and physicaltesting of walls for in-plane loading.
C4.1.6 Termination of Reinforcement
The requirement that vertical wall reinforcement beterminated with a standard hook where the factored roofuplift force from Table 7.1A exceeds 1,000 plf (14.60 kN/m)is based on current standards for conventional masonryconstruction. The requirement has proven very effective inmasonry construction in conditions with wind speeds of 110mph (49 m/s) or greater. In the predecessor to this Standard,the requirement for hooks was triggered at a design windpressure greater than 40 psf (1.92 kN/m2). This trigger waschosen over the 110 mph (49 m/s) trigger since the designwind pressure can vary significantly at any specific basic windspeed depending upon exposure category as illustrated inthe table in Section C4.1. However, as indicated in Table 7.1A,the uplift force resulting from a given basic wind speed andexposure category can also vary significantly depending uponthe roof slope and dimension of the building in the directionof the wind. In reviewing Table 7.1A, it was noted that for agiven velocity pressure, the maximum roof uplift force occursat a roof slope of 20 degrees or 4.4 in 12. At this slope theexternal pressure coefficient, GCpf, on the windward roofsurface within a distance of 2a of the corner is -1.07. Sincethe design wind pressure is the product of the velocity pres-
sure and GCpf – GCpi (-1.07 – (+0.18) = -1.25), the velocitypressure corresponding to a design pressure of 40 psf (1.92kN/m2) is 32 psf (1.53 kN/m2) (40/1.25 = 32). Based on Table7.1A, for a velocity pressure of 31.79 psf (1.52 kN/m2), themaximum factored uplift force for portions of the wall withindistance 2a of the corner is 892 plf (13.02 kN/m), and allow-ing an additional 108 plf (1.58 kN/m) for an overhang resultsin an uplift force of 1,000 plf (14.60 kN/m). Based on this, itwas decided to trigger the requirement for standard hookson vertical wall reinforcement at this value. The hook allowsthe full tensile strength of the reinforcing bar to be developedand therefore provides additional tensile strength in the con-crete wall to resist the large roof uplift forces in high windareas. A similar detailing requirement is used in high seismicconditions as required in ACI 318 [C4.1].
C4.1.7 Location of Reinforcement in Wall
The amount of reinforcement required by the tables in thischapter for a given condition of wall type, height, thickness,and eccentricity of loads supported was computed based onthe centroid of the vertical reinforcement being at the centerof the wall. In engineering terms, the effective depth, d, wasone-half the wall thickness. The predecessor to this Standardrequired the reinforcement to be located within the centerone-third of the wall thickness. Depending upon how thiswas interpreted, this allowed the centroid of the verticalreinforcement to vary by up to one-sixth the wall thicknessfrom the location assumed in the calculations. This meantthat the effective depth for a 6-inch (152 mm) wall wasreduced one inch (25.4 mm) if the reinforcement was posi-tioned toward the flexural compression side of the wall. Thisamounted to a reduction in d of approximately 33%. Sincedesign moment strength is approximately proportional tothe effective depth, this misplacement of the reinforcementfrom where it was assumed in the design resulted in anapproximately 33% reduction in design moment strength.
This Standard requires that the vertical reinforcement beplaced at the center of the wall with a tolerance of thelarger of 10% of the wall thickness and 3⁄8-inch (10 mm).The latter criterion is based on the tolerance on d in ACI 318[C4.1] for members with effective depth, d, less than orequal to 8 inches (203 mm). Since this Standard hasprovisions for 31⁄2-inch (89 mm) walls, the ACI 318 [C4.1]tolerance of 3⁄8-inch (10 mm) is approximately 10% of thewall thickness. Based on this, it was decided that if 10%tolerance was permitted for a very thin wall, then it shouldalso be acceptable for thicker walls.
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REFERENCESC4.1 Building Code Requirements for Structural Concrete
(ACI 318-05) and Commentary (ACI 318R-05).American Concrete Institute, Farmington Hills,Michigan. 2004.
C4.2 Minimum Design Loads for Buildings and OtherStructures, including Supplement No. 1 (ASCE/SEI7-05). American Society of Civil Engineers, Reston,Virginia. 2005.
C4.3 International Building Code, 2006 Edition. InternationalCode Council (ICC), Falls Church, Virginia. 2006.
C4.4 Design Criteria for Insulating Concrete Form WallSystems, (RP 116). Prepared for the Portland CementAssociation by Construction Technology Laboratories,Inc., Skokie, Illinois. 1996.
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CHAPTER 5 COMMENTARY –SOLIDWALLS FOR RESISTANCE TOLATERAL FORCES
C5.1 LENGTHOF SOLIDWALLThe tables in Chapters 3 and 4 are based on concrete wallswithout door or window openings. This simplified approachrarely arises in residential construction since walls generallycontain windows and doors to meet functional needs. Theamount of openings affects the lateral (racking) strength ofthe building parallel to the wall, which resists wind andseismic forces. The Standard addresses the minimum amountof solid wall required to resist in-plane shear loads from windand seismic forces. Provisions for the amount and placementlocation of additional reinforcement required aroundopenings are found in Chapter 7.
TABLES 5.1A, B and C – Tables 5.1A, B and C are basedon the analytical procedure (method 2) of the wind load provi-sions of ASCE 7 [C5.2] for low-rise buildings. ASCE 7 definesa low-rise building as an enclosed or partially enclosed build-ing with a mean roof height of less than or equal to 60 feet(18.3 m) in which the mean roof height does not exceed theleast horizontal dimension. The following table shows thevelocity pressures for the various basic wind speeds and ex-posure categories and how they were grouped for purposesof designs in this Standard. The velocities pressures are basedon a building with a mean roof height of 35 feet (10.7 m).The values in the shaded cells were used to compute the in-plane forces to be resisted by solid walls in each of the twoexterior wall lines parallel to the direction of the wind. Thebasic wind speeds shown in the table in italics represent thevalues required to produce the velocity pressure for thevarious exposure categories that are equal to the value that
is �s�h�a�d�e�d . Although the highest basic end speed shown inFigure 6-1 of ASCE 7 for the 50 states of the United States is150 mph (67 m/s), 170 mph (76 m/s) is listed in the figure tobe used for Guam.
To compute the forces, external pressure coefficients, GCpf,from Figure 6-10 of ASCE 7 [C5.2] were used to calculatethe design wind pressures for various building surfaces andthese pressures were applied to the building as shown inFigure 6-10. The following assumptions were used to calcu-late the forces.
1. Floor-to-ceiling wall heights (all stories) – 10 feet (3.0 m)
2. Thickness of second floor assembly, if applicable – 16inches (406 mm)
3. Thickness of attic floor/ceiling assembly above the topstory ceiling – 12 inches (305 mm)
4. Width of roof overhang (when computing wind forcesperpendicular to ridge) – 24 inches (610 mm)
ASCE 7 [C5.2] requires that the main wind-force-resistingsystem be designed for the larger of the forces computedas describe above, and a force of 10 psf (0.48 kN/m2) multi-plied by the area of the building projected onto a verticalplane normal to the assumed wind direction. The minimumforce generally governs for the design of buildings havinglower sloped roofs (i.e., approximately 5 in 12 (23 degrees)or less) sited in areas with lower basic wind speeds, asillustrated by the shaded cells in Tables 5.1A, B, and C.
The forces computed as described above were divided by840 plf (12.26 kN/m) to obtain the unadjusted lengths ofsolid wall tabulated in Tables 5.1A, B, and C. See thecommentary below on Tables 5.4A and B on how the ad-justment factor, F, in those tables was derived. The value of840 (12.26) was used because it was the basis of the devel-opment of the F factors and maximizes the unadjusted solidwall lengths in Tables 5.1A, B, and C.
TABLE 5.2 – Since Tables 5.1A, B, and C are based on abuilding with a mean roof height of 35 feet (10.7 m), Table5.2 provides reduction factors for buildings with a mean roofheight of less than 35 feet (10.7 m). The reduction factor, ifapplicable, is multiplied by the unadjusted solid wall lengthshown in Tables 5.1A, B, and C.
TABLE 5.3 – Since Tables 5.1A, B, and C are based on floor-to-ceiling wall heights of 10 feet (3.0 m), Table 5.3 providesreduction factors for floor-to-ceiling wall heights of less than10 feet (3.0 m). The reduction factor, if applicable, is
Basic wind speed – mph Velocity pressure – psfExposure category Exposure category
B C D B C D85 11.5190 12.90
100 85 15.93 15.95110 90 85 19.28 17.88 18.77120 100 90 22.94 22.08 21.04130 110 100 26.92 26.72 25.98140 120 110 31.23 31.79 31.43150 130 120 35.85 37.31 37.41166 140 130 43.27 43.90179 150 140 49.68 50.91192 163 150 58.45
For SI: 1 mph = 0.4470 m/s 1 psf = 0.0479 kN/m2
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multiplied by the unadjusted solid wall length shown inTables 5.1A, B, and C.
TABLE 5.4A for FLAT WALLS – Previous prescriptivemethods do not recognize that different lengths of solid wallsegments and different amounts of vertical reinforcementnear the end of a segment of the same length generallyincrease the design strength with regard to the in-planeforce the segment is capable of resisting. In order to recog-nize these benefits, solid wall segments of different lengths,thicknesses, number and size of bars at the ends of thesegments, and presence or absence of horizontal shear rein-forcement were evaluated. Segments were evaluated ascantilevered flexural elements fixed at the base with a heightof 8 feet (2.4 m). It was felt that 8 feet (2.4 m) was a reason-able height to use for this calculation, even where the floor-to-ceiling wall height may be 10 feet (3.0 m), because thetops of most wall openings are 8 feet (2.4 m) or less abovethe floor. Design moment strengths for solid wall segmentsin flat walls were computed based on the parameters listedbelow and as enumerated in Table 5.4A.
1. Solid wall segment length
2. Segment thickness (i.e., nominal thickness minus one-half inch (13 mm))
3. Number of reinforcing bars at end of segment and theirlocation
4. Size of reinforcing bars at end of segment
5. Yield strength of reinforcement
6. Specified compressive strength of concrete
Using these parameters, design moment strengths werecomputed for each unique solid wall segment combinationshown in Table 5.4A. Where minimum tensile reinforcementwas not being provided in accordance with Section 10.5.1 ofACI 318 [C5.1], calculated design moment strengths werereduced by 25%. This meant that the amount of steelprovided was one-third more than required by analysis aspermitted by Section 10.5.3 of ACI 318 in order to waive theminimum steel requirements of Section 10.5.1. The area oftensile reinforcement was checked to make sure that thesection was tensioned controlled so that a strength reductionfactor of 0.90 could be used (see Sections 9.3.2.1 and10.3.4 of ACI 318). The design moment strength wasdivided by the assumed height of the solid wall segment(i.e., 8 feet (2.4 m)) and by the length of the solid wallsegment to determine a design strength per linear foot of
length of the segment. This is the force (per foot of length ofthe segment) that can be applied at the top of the solid wallsegment in the plane of the wall.
Next the design shear strength was computed for the samesolid wall segment. Since only nominal horizontal reinforce-ment is required in walls of buildings assigned to SeismicDesign Category A or B, and detached one-and two-familydwellings assigned to Seismic Design Category C, no shearreinforcement was assumed (see Sections 4.1.2 and 4.1.3).This required that the design shear strength be computedbased on 0.5φφVc in accordance with Section 11.10.8 of ACI318 [C5.1]. Section 11.10.4 of ACI 318 requires that forshear walls, the distance from the extreme compression fiberto the centroid of longitudinal tension reinforcement, d, betaken equal to 0.8 times the length of the solid wall segment.Generally this provision dictates the use of a d less than thatused to compute moment strength and results in a lowervalue of Vc than would otherwise be computed. Sincemoment strength computations only considered the verticalbars at the end of the solid wall segment, with d alwaysbeing greater than 0.8 times the solid segment length, it wasdecided to use the same d for calculating shear strength asused to compute moment strength. Design shear strength,φφVc, was computed based on Section 11.10.5 of ACI 318 forwalls subject to axial compression. The design shear strengthwas divided by the length of the solid wall segment to deter-mine a design shear strength per linear foot of length of thesegment. This is the force (per foot of length of thesegment) that can be applied at the top of the solid wallsegment in the plane of the wall. The two design strengths(based on moment and shear) per linear foot of length ofsolid wall segment were compared, and the lower of thetwo values used for that unique solid wall segment.
TABLE 5.4B for WAFFLE- and SCREEN-GRID WALLS –Table 5.4B for waffle- and screen-grid walls was developed ina similar fashion to Table 5.4A except as noted as follows.Design moment strengths of solid wall segments werecomputed based on the assumption of a flanged section.The flange width in the through-the-wall dimension wasassumed to be 5.5 inches (140 mm) for 6-inch (152 mm)waffle- and screen-grid walls, and 7.5 inches (191 mm) for8-inch (203 mm) waffle-grid walls. The depth of the concretecompression zone, a, was computed to ensure that asufficient depth of concrete (in the in-plane direction) isprovided in the area of the segment under compression.“Sufficient depth” is assured in the field by complying withnote 9 of Table 5.4B. For computing minimum flexural steel
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requirements of Section 10.5.1 of ACI 318 [C5.1], the provi-sions of Section 10.5.2 of ACI 318 were followed.
In the predecessor to this Standard, the design shearstrength (based on concrete alone) of solid wall segmentswas computed based on the area of the vertical core ofconcrete. In this Standard, the design shear strength (basedon concrete alone) of solid wall segments was computedbased on an assumed web thicknesses of 2.6 inches (66 mm)for 6-inch (152 mm) and 8-inch (203 mm) nominal waffle-grid walls and 2.2 inches (56 mm) for 6-inch (152 mm)nominal screen-grid walls. These values, which are based onrecommendations contained in Testing and Design of LintelsUsing Insulating Concrete Forms [C5.3], give some credit tothe flanges for their contribution in resisting shear stressesthat is not accounted for in the provisions of ACI 318.
TABLES 5.4A and B – Development of adjustmentfactor, F – After the allowable loads for all the solid walltypes in Table 5.4A (flat walls) and Table 5.4B (waffle- andscreen-grid walls) were computed, they were compared andthe lowest value selected. The lowest value was for a 6-inch(152 mm) nominal screen-grid wall having a length of 24inches (610 mm), with three No. 4 bars at each end with ayield strength of 40,000 psi (280 MPa), constructed withconcrete having a specified compressive strength of 2,500psi (17.2 MPa), and no horizontal shear reinforcement. Thevalue for that wall was 839 plf (rounded to 840) (12.26kN/m), and was controlled by shear strength of the concrete.The controlling value for all wall types in Tables 5.4A and Bwas divided by 840 to obtain the adjustment factor, F, forthe particular wall type.
TABLES 5.4A and B – Columns are provided in the tablesfor vertical reinforcement with yield strengths of 40,000 psi(280 MPa) and 60,000 psi (420 MPa). Note 6 calls attentionto the requirement of Section 4.1.3 that reinforcement in allbuildings assigned to Seismic Design Category D0, D1 or D2
must have a minimum yield strength of 60,000 psi (420MPa). Factors are provided for conditions where horizontalshear reinforcement is and is not provided. Note 4 callsattention to the requirement of Section 4.1.3 that multipledwellings assigned to Seismic Design Category C and allbuildings assigned to Seismic Design Category D0, D1 or D2,must have horizontal shear reinforcement. The basic require-ment of the standard is that concrete have a specifiedcompressive strength, f'c, of not less than 2,500 psi (17.2MPa); therefore, design shear strength of concrete is basedon this value. Note 7 calls attention to the requirement ofSection 4.1.4 that f'c in buildings assigned to Seismic Design
Category D0, D1 or D2 must be not less than 3,000 psi (20.7MPa); therefore, an increase in the F factor is permitted totake advantage of the higher strength concrete. The adjust-ment factors in the column for Seismic Design Category Dreflect the lower strength reduction factor, φφ, required forshear (0.60 versus 0.75) for buildings assigned to SeismicDesign Category D0, D1 or D2 as required by Section 9.3.4(a)of ACI 318 [C5.1].
TABLES 5.5A, B and C – Tables 5.5A, B and C are basedon the provisions of the simplified alternate structural designcriteria for simple bearing wall or building frame systems ofSection 12.14 of the seismic load provisions of ASCE 7[C5.2]. Since Section 1.2.2, item #1 of this Standardprohibits the aspect ratio of multiple dwellings assigned toSeismic Design Category C and all buildings assigned toSeismic Design Category D0, D1 or D2 from exceeding two,the table is based on the area of the building within theexterior walls. As the aspect ratio of a rectangle with thesame area increases from one to 2, the perimeter onlyincreases by approximately 6 percent. However, the perimeterwalls are not the only items that contribute mass to thebuilding. When the interior walls, floor and roof are takeninto account, the mass of the building only increases a couplepercent as the aspect ratio increases from one to 2.Therefore, basing the table on areas with an assumed aspectratio of 2 will result in designs that are not overly conserva-tive if the actual building has an aspect ratio of one. Otherassumptions used to develop the table include:
1. Floor-to-ceiling wall height (all stories) – 10 feet (3.0 m)
2. Thickness of second floor assembly (if applicable) – 16inches (406 mm)
3. Thickness of exterior walls (for computing roof overhangarea and mass beyond inside surface of exterior walls) –9 inches (229 mm)
4. Horizontal extension of roof overhang beyond exteriorsurface of exterior wall (all four edges) – 24 inches(610 mm)
5. The following dead loads were used:
a. Floor assembly – 10 psf (0.48 kN/m2)
b. Roof/ceiling assembly – 15 psf (0.72 kN/m2)
c. Roof overhangs – 8 psf (0.38 kN/m2)
d. Interior partition allowance – 10 psf (0.48 kN/m2) persquare foot (m2) of floor area per story
e. Doors and windows in exterior walls – 4 psf (0.19kN/m2)
f. Concrete exterior walls
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Appendix C – Commentaries
i. wall group 1 (6-inch (152 mm) waffle-grid and6-inch (152 mm) screen-grid) – 56 psf (2.68 kN/m2)
ii. wall group 2 (6-inch (152 mm) flat and 8-inch (mm)waffle-grid) – 76 psf (3.64 kN/m2)
iii.wall group 3 (8-inch (203 mm) flat) – 100 psf(4.79 kN/m2)
iv. wall group 4 (10-inch (254 mm) flat) – 125 psf(5.99 kN/m2)
g. Finishes added to exterior concrete walls
i. interior wall finish – 2 psf (0.10 kN/m2)
ii. exterior wall covering – 11 psf (0.53 kN/m2)
h. Light framed exterior walls, including interior finishand exterior wall covering (second story walls, whereapplicable, and gable portion of end walls in all cases)– 15 psf (0.72 kN/m2)
6. Ground snow load - 70 psf (3.35 kN/m2)
7. Percent of doors and windows in exterior wall area(portion between floor and ceiling) – 15%
8. Roof slope – 9 in 12 (36.9 degrees)
The International Residential Code [C5.5] limits the weight ofexterior walls of light-framed construction for purposes ofthe code’s prescriptive seismic design provisions to 15 psf(0.72 kN/m2). It was determined that 15 psf (0.72 kN/m2)was adequate for an exterior wall covering of cement stuccoof the thickness required by the code (i.e., 7⁄8-inch (22 mm)).
For purposes of determining the weight of the light-framedgable portion of the endwalls (perpendicular to the ridge), aroof slope of 9 in 12 (36.9 degrees) was assumed. If was feltthat using a slope that is slightly less than the maximumpermitted by the Standard (i.e., 12 in 12 (45 degrees)) was afair compromise that would not jeopardize safety should aroof slope steeper than 9 in 12 be used, or unduly penalize abuilding with a roof slope less than 9 in 12. Also consideredwas the fact that very few homes are constructed with roofslopes of more than 9 in 12 (36.9 degrees). For a flat roof,use of the 9 in 12 slope results in the base shear being over-estimated approximately 3 percent, and for a roof slope of12 in 12, use of the 9 in 12 slope results in the base shearbeing under-estimated approximately 2 percent.
It was assumed that solid wall segments in compliance withthe provisions of this Standard comply with the requirementsof ASCE 7 [C5.2] for ordinary reinforced concrete shear walls,which are minimum requirements for buildings assigned toSeismic Design Category C. Therefore, for multiple dwellingsassigned to Seismic Design Category C, a response modifica-
tion coefficient, R, of 4 from Table 12.14-1 of ASCE 7 wasused. It was assumed that solid wall segments in compliancewith the provisions of this Standard comply with the require-ments of ASCE 7 for special reinforced concrete shear walls,which are minimum requirements for buildings assigned toSeismic Design Category D0, D1 or D2. Therefore, for allbuildings assigned to Seismic Design Category D0, D1 or D2,a response modification coefficient, R, of 5 from Table12.14-1 of ASCE 7 was used.
Using the above assumptions and parameters in the table,the seismic base shear, V, was computed in accordance withSection 12.14.8.1 of ASCE 7 [C5.2], and then distributed tothe solid walls in the applicable story in each of the twoexterior wall lines parallel to the direction of the groundmotion in accordance with Section 12.14.8.2 of ASCE 7. Theforces computed were then divided by 840 plf (12.26 kN/m)to obtain the unadjusted lengths of solid wall tabulated inTables 5.5A, B and C. See commentary above on how the Ffactors in Table 5.4A were derived to see why the value of840 (12.26) was used.
Since the simplified seismic design provisions of ASCE 7[C5.2] require that the base shear be amplified by 10% for a2-story building, note 2 of Table 5.5A permits the tabulatedunadjusted solid wall length to be multiplied by 0.91(1/1.1 = 0.91) for a one story building.
TABLE 5.6A and B – Since Tables 5.5A, B and C are basedon floor-to-ceiling wall heights of 10 feet (3.0 m), Tables5.6A and B provide reduction factors, R5.6, for floor-to-ceiling wall heights of less than 10 feet (3.0 m). The reduc -tion factor, if applicable, is multiplied by the unadjusted solidwall length shown in Tables 5.5A, B and C.
TABLE 5.7 – Since Tables 5.5A, B, and C are based on anexterior wall covering weighing 11 psf (0.53 kN/m2) (e.g., 7⁄8-inch (22 mm) of cement stucco), Table 5.7 provides reductionfactors, R5.7, for exterior wall coverings weighing 3 psf (0.14kN/m2) or less (e.g., vinyl siding and some fiber-cementsiding). The dead load of portions of exterior walls of lightframe con struction was assumed to be 8 psf (0.38 kN/m2)when considering an exterior wall covering weighing 3 psf(0.14 kN/m2) or less. For exterior wall coverings weighingbetween 3 (0.14) and 11 psf (0.53 kN/m2), the reductionfactor can be determined by interpolation. The reductionfactor, if applicable, is multiplied by the unadjusted solid walllength shown in Tables 5.5A, B and C.
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TABLE 5.8 – Since the portions of Tables 5.5A, B, and Cthat apply where the ground snow load is between 40 (1.92)and 70 psf (3.35 kN/m2) are based on a ground snow of 70psf (3.35 kN/m2), Table 5.8 provides reduction factors, R5.8,for a ground snow load of 40 psf (1.92 kN/m2). Where theground snow load is between 40 (1.92) and 70 psf (3.35kN/m2), the reduction factor can be determined by interpola-tion. The reduction factor, if applicable, is multiplied by theunadjusted solid wall length shown in Tables 5.5A, B and C.
C5.2 SOLID WALL SEGMENTSProvisions for limited openings in solid wall segments recog-nize the reality that mandating a segment with no openingsis not practical. Prohibiting the opening within 6 inches(152 mm) of the edge of a solid wall segment is intendedto prevent holes from reducing the area of concrete in thecompression zone.
C5.2.1.2 Seismic Design Category C
For multiple dwellings assigned to Seismic Design CategoryC, only solid wall segments in the wall line that are a mini -mum 36 inches (914 mm) in length are to be included in thetotal wall length contributing to lateral load resistance. Theseminimum lengths are based on tested performance reportedin In-Plane Shear Resistance of Insulating Concrete FormWalls [C5.4].
C5.2.1.3 Seismic Design Category D0, D1 or D2In all buildings assigned to Seismic Design Category D0, D1
or D2, only solid wall segments in the wall line that are aminimum 48 inches (1.2 m) in length are to be included inthe total wall length contributing to lateral load resistance.These minimum lengths are based on tested performancereported in In-Plane Shear Resistance of Insulating ConcreteForm Walls [C5.4].
C5.2.2 Reinforcement in Solid Wall Segments
For buildings assigned to Seismic Design Category A or B,and for detached one-and two-family dwellings assigned toSeismic Design Category C, there are two options withrespect to horizontal shear reinforcement. If the option touse no horizontal shear reinforcement is assumed in selectingthe F factor from Table 5.4A or B, horizontal and verticalreinforcement must be provided in accordance with Sections4.1.2 and 5.2.2. On the other hand, if the option to usehorizontal shear reinforcement is assumed in selecting the Ffactor from Table 5.4A or B, horizontal and vertical reinforce-ment must be installed in accordance with Sections 4.1.3
and 5.2.2. For multiple dwellings assigned to Seismic DesignCategory C, and all buildings assigned to Seismic DesignCategory D0, D1 or D2, horizontal and vertical reinforcementin accordance with Sections 4.1 3 and 5.2.2 must beprovided in all cases.
REFERENCESC5.1 Building Code Requirements for Structural Concrete
(ACI 318-05) and Commentary (ACI 318R-05).American Concrete Institute, Farmington Hills,Michigan. 2004.
C5.2 Minimum Design Loads for Buildings and OtherStructures, including Supplement No. 1, ASCE/SEI 7-05.American Society of Civil Engineers, Reston, Virginia.2005.
C5.3 Testing and Design of Lintels Using Insulating ConcreteForms. Prepared for the U.S. Department of Housingand Urban Development, Portland Cement Association,and the National Association of Home Builders by theNAHB Research Center, Inc., Upper Marlboro,Maryland. 2000.
C5.4 In-Plane Shear Resistance of Insulating Concrete FormWalls. Prepared for the U.S. Department of Housingand Urban Development, Portland Cement Association,and the National Association of Home Builders by theNAHB Research Center, Inc., Upper Marlboro,Maryland. 2001.
C5.5 International Residential Code for One- and Two-FamilyDwellings, 2006 Edition, Interna tional Code Council(ICC), Falls Church, Virginia. 2006.
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Appendix C – Commentaries
CHAPTER 6 COMMENTARY –REQUIREMENTS FOR CONNECTIONSAND DIAPHRAGMS
C6.2 FOUNDATION WALL-TO-FOOTING CONNECTIONThe requirements of the Standard are based on typical resi -dential construction practice for light-framed construction.Due to the heavier axial loads of walls of concrete construc-tion, frictional resistance at the footing-wall interface ishigher and provides a greater factor of safety than in light-framed residential construction, except for buildings assignedto Seismic Design Category D0, D1 or D2 where dowels arerequired.
C6.4 CONNECTIONS BETWEENCONCRETE WALLS AND LIGHT-FRAMED FLOOR SYSTEMSSection 6.4 provides four approaches for designing anchor-ages between concrete walls and light-framed floor con -struc tion. First, prescriptive details are provided in Figures 6.3through 6.6 for floors of wood frame construction and inFigures 6.7 through Figure 6.10 for cold-formed steel framedfloor systems. Each prescriptive detail may only be usedwhere permitted by the table accompanying that figure. Theprescriptive details are based on the tabulated ASD loads inAppendix A and address loads in three directions occurringsimultaneously (horizontal in the plane of the wall, hori -zontal out-of-plane, and vertical). The second approach (item3) allows selection of proprietary connection hardware basedon loads given in Appendix A or Appendix B. The thirdapproach (item 4) allows engineered anchorage design tomeet the loads tabulated in Appendix A or Appendix B. Thefourth approach (item 5) involves an engineered design forthe specific building configuration.
The loads in Appendix A and Appendix B are based on theloading requirements of ASCE 7 [C6.1]. Loads are based onworst-case conditions for buildings with floor and roofaspect ratios of up to 2:1 and with roof angles rangingbetween zero and 45 degrees. It may be possible to calculatelower loads than tabulated for a specific building configura-tion. Calculations of anchorage design strength (capacity) arebased on ACI 318 [C6.2] and the AISI S100 [C6.3] for cold-formed steel, and AF&PA/NDS [C6.4] for wood frameconstruction. ACI 318 anchorage to concrete provisionsseverely reduce concrete anchor capacity near concrete
edges. This reduction in capacity is particularly significantwith ICF screen- and waffle-grid walls because of the edgeconditions created by the core construction. For this reason,the prescriptive details require that ICF web material beremoved in the vicinity of the anchorage. The area of webremoved is indicated by cross-hatching in the figures.
C6.5 CONNECTIONS BETWEENCONCRETE WALLS AND LIGHT-FRAMED CEILING AND ROOFSYSTEMSSection 6.5 provides the same four approaches for ceilingand roof systems as Section 6.4 provides for floor systems.See Section C6.4 for applicable commentary.
C6.6 FLOOR, ROOF AND CEILINGDIAPHRAGM CONSTRUCTIONResistance for wind and seismic forces relies on wood struc-tural panel diaphragms at the roof and floors. In some cases,blocked diaphragms are necessary in order to develop theshear strength required. Where gable endwalls occur, woodstructural panel ceiling diaphragms are relied on to supportthe top of the concrete gable endwall, in addition to thesupport provided by the roof diaphragm. In addition to basicdiaphragm construction, wood structural panel sheathingneeds to be fastened at the noted edge-nail or edge-screwspacing to the framing members to which tension ties areattached.
Section 6.6.1 provides guidance for floor diaphragms usingeither wood framing or cold-formed steel framing. Section6.6.2 provides guidance for roof and ceiling diaphragmsusing either wood framing or cold-formed steel framing.Section 6.6.3 provides guidance on construction details forblocked diaphragms, where they are required by Table 6.1,6.2, 6.3 or 6.4. Section 6.6.4 provides guidance for contin -uous ties across diaphragms required by ASCE 7 [C6.1] inbuildings assigned to a higher seismic design category. Itshould be noted that in the direction parallel to the mainframing members, it is assumed that the framing membersprovide the continuous ties. Therefore, it is essential thatwhere framing members are not continuous across thebuilding, discontinuous ends must be lapped and fastened,or otherwise attached to provide the continuity assumed.
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REFERENCESC6.1 Minimum Design Loads for Buildings and Other
Structures, including Supplement No. 1, ASCE/SEI7-05. American Society of Civil Engineers, Reston,Virginia. 2005.
C6.2 Building Code Requirements for Structural Concrete(ACI 318-05) and Commentary (ACI 318R-05).American Concrete Institute, Farmington Hills,Michigan. 2004.
C6.3 North American Specification for the Design of Cold-Formed Steel Structural Members, AISI S100-07,American Iron and Steel Institute, Washington, DC.2007.
C6.4 National Design Specification (NDS) for Wood Con -struc tion with Commentary and NDS SupplementDesign Values for Wood Construction, ANSI/AF&PANDS-2005. American Wood Council, American Forest& Paper Association, Washington, D.C. 2005.
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Appendix C – Commentaries
CHAPTER 7 COMMENTARY –REQUIREMENTS FOR LINTELS ANDREINFORCEMENT AROUNDOPENINGS
C7.1 REINFORCEMENT AROUNDOPENINGS
The requirements for number of bars and placement ofreinforce ment around openings are based on ACI 318 [C7.1]with some adjustments. ACI 318 [C7.1] requires two No. 5bars on each side of all window and door openings. Pre -sumably this reinforcement is to control cracks that mayemanate from the corners of an opening. In addition,adding the number and size of bars required by ACI 318[C7.1] is impractical for some types of forming systemsused in residential construction.
C7.1.2 Vertical Reinforcement
The requirement for some vertical reinforcement adjacent toopenings in all buildings is to provided resistance to roofuplift loads. The roof uplift forces in Table 7.1A were calcu-lated as follows. External pressure coefficients, GCpf, fromFigure 6-10 of ASCE 7 [C7.2] for the main wind force re -sisting system were applied to the exterior of the roof surfaces.A positive internal pressure coefficient, GCpi, of +0.18 wasincluded as required by ASCE 7 for enclosed buildings. Theroof/ceiling dead load was assumed to be 15 psf (0.72 kN/m2),and the dead load of the roof overhang was assumed to be8 psf (0.38 kN/m2). Velocity pressures for exposure cate -gories B, C and D were computed for basic wind speeds of85 mph (38 m/s), 90 mph (40 m/s), and thereafter in incre -mental increases of 10 mph (4.47 m/s) though 150 mph (67m/s). Velocity pressures across the three exposures that wereapproximately the same were grouped and the highest pres-sure within that group was used for the calculations. Thevelocity pressures are based on a mean roof height of 35feet (10.7 m); however, note 4 to Table 7.1A permits theuplift values to be reduced if the actual mean roof height isless than 35 feet (10.7 m). The velocity pressures used areshown at the top of the Table 7.1A. See Section C5.1 foradditional informa tion on the derivation of velocity pressures.The governing strength design load combination for roofuplift from ACI 318 [C7.1] and ASCE 7 is 0.9D + 1.6W.
Roof uplift forces were calculated by summing moments atthe top of the leeward and windward walls for wind blowingperpendicular to the ridge. For wind blowing parallel to the
ridge, uplift forces were determined by summing momentsat the top of the wall on the opposite side of the buildingfrom where the higher edge-strip (i.e., distance 2a) pressureswere applied (see Figure 6-10 of ASCE 7 [C7.2]. The greateruplift force calculated is the governing condition shown inTable 7.1A. The maximum roof uplift occurs at thewindward wall (moment summed at top of leeward wall)with wind blowing perpendicular to the ridge, for endportions of buildings (i.e., within distance 2a of the corner)where the roof slope is less than or equal to 4.4 in 12 (20degrees) with no overhang. These are the uplift forcesshown in Table 7.1A for portions of the building withindistance 2a of the corner where the roof slope is less than5.6 in 12 (25 degrees). For portions of the wall more thandistance 2a from the corner for roof slopes less than 5.6 in12 (25 degrees), and for all portions of the wall for roofslopes equal to or greater than 5.6 in 12 (25 degrees), themaximum roof uplift occurs with wind blowing parallel tothe ridge, with the roof slope assumed to be zero inaccordance with Note 7 of Figure 6-10 of ASCE 7.
Instead of developing a table of uplift forces that includedifferent overhang projections, an approximate method hasbeen utilized to simplify the inclusion of roof uplift con -tributed by overhangs. Rather than including the overhangs’effects in the summation of moments, the design pressuresdue to the wind acting on the top surface, less the deadload of the overhang, is added to the uplift computed basedon the building having no overhangs. In addition, for roofslopes less than or equal to 5.6 in 12 (25 degrees), a GCpvalue of +0.68 (where G = 0.85 and Cp = +0.8) has beenincluded on the underside of the windward roof overhang asrequired by Section 6.5.11.4.1 of ASCE 7 [C7.2]. The simpli-fied procedure results in the uplift contributed by theoverhang being slightly underestimated, with the error beingapproximately proportional to the ratio of the horizontalprojection of the overhang and the width of the building.For example, the error for a 2-foot (610 mm) overhang on abuilding 40 feet (12.2 m) wide is 2.5% ((1/40) x 100 = 2.5,where 1 is one-half the horizontal projection). As thehorizontal projection increases and/or the building widthdecreases, the percentage error increases. The error is some-what mitigated since the counteracting effect of theoverhang on the edge of the roof at the wall wheremoments are summed is neglected. The overhang upliftforces were calculated using GCpf values for a roof slope of4.4:12 (20 degrees), which represents the worst-case condi-tion.
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Some prescriptive standards permit a constant reduction(e.g., 40%) in uplift force for wall areas more than distance2a from the corner. Distance “a” is defined in Note 2 ofTable 7.1A which is taken from a note to Figure 6-10 ofASCE 7 [C7.2]. As illustrated by a comparison of the valuesin the two portions of Table 7.1A, a simple approach suchas that can be very unconservative.
Table 7.1B was developed as follows. Factored uplift forcesat each end of a lintel were calculated using the two para -meters shown in the table. The uplift force at each end is theproduct of the roof uplift force per linear foot of wall fromTable 7.1A and one-half the lintel clear span. The dead loadof the lintel was ignored. Next, design tensile strengths werecomputed for the various number of bars, bar sizes, andgrades of steel shown in Table 7.1B. The design tensilestrength is the product of the area of bar(s), the yield strengthof steel and the strength reduction factor (i.e., 0.90). Thedesign tensile strength of 2-#4 bars and 1-#6 bar was basedon the area of 2-#4 bars which is slightly less than that of1-#6 bar. Finally, the number of bars, bar size and grade ofsteel was determined by finding a combination that had adesign tensile strength that was equal to or greater than thefactored uplift force at the end of the lintel.
C7.2 LINTELS
C7.2.1 Lintels Designed for Gravity Load-Bearing Conditions
Lintels are horizontal members used to transfer wall, floor,roof, and attic dead loads, snow and live loads above open-ings in walls to the sides of the opening. Lintel clear spans inTables 7.3 through 7.16 are based on five loading conditions.The appropriate loading condition to be used is determinedfrom Table 7.2.
In developing the loading conditions of Table 7.2, archingaction above the opening was considered. Based on thisconcept, the lintel only supports the weight of the concreteabove the lintel bounded by a triangle with its basecorresponding to the clear span of the lintel, and sides whichstart at the top of the lintel at the edges of the opening andextend upward and inward toward the center of the openingat an angle of 45 degrees. Given this geometry, the apex ofthe triangle is on the centerline of the opening and theheight of the triangle is one-half the opening width.Therefore, in order to consider arching action, the height ofthe wall above the top of the lintel must be greater than
one-half the opening width. Where arching action can beconsidered and there are no loads introduced into the trian-gular area, Table 7.2 indicates that the lintel is to be designfor a nonload-bearing condition (NLB). If loads are imposedon the wall within the triangular area beneath the arch, suchas from a floor ledger board bolted to the side of the wall,the lintel must also be designed for the dead and live loadssupported by the ledger; loading condition #1 of Table 7.2. Ifthe lintel is near the top of a concrete wall that is supportinga roof, and the height of concrete above the top of the lintelis equal to or less than one-half the opening width, the lintelmust be designed for roof loads which is loading condition#2 of Table 7.2.
In many instances openings are stacked such that anopening in the story below is within the footprint or shadowof the opening above. The width of the lower opening maybe less than or equal to the width of the opening above.Where the height of the wall between the top of the lintel ofthe lower opening and bottom of the upper opening is equalto or less than one-half the width of the lower opening,arching action cannot be considered. In this case, the lintelabove the lower opening is designed to support the weightof the wall between the openings (NLB loading condition). Ifa load is imposed on the wall between the two openings,such as from a ledger board, loading condition #1 must beused. In cases other than stacked openings where there isinsufficient height above the top of the lintel to develop anarch, such as near the top of the wall at the roof (loadingcondition #2), or where an opening above is too close topermit the arch to develop, the lintel must be designed forthe weight of the wall above the lintel and any loadsimposed on the wall above, whether introduced via a ledgerboard or on top of the wall. Depending upon where theopening in question is located, this may require the lintel tobe designed for roof loads and one floor (loading condition#4) or roof and two floors (loading condition #5). Loadingcondition #3 of Table 7.2 is included for the situation wherethe second story exterior wall is of light-framed construction.Typically in this situation a lintel above an opening in the firststory supports the second floor which usually bears on top ofthe wall, and dead, live and snow loads from the roof, atticand light-framed second story exterior wall.
The five (5) loading conditions of Tables 7.3 through 7.16can be summarized as follows:
1. Design for floor load only
2. Design for roof load only
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Appendix C – Commentaries
3. Design for loads from roof, attic, lighted framed secondstory exterior wall and second floor
4. Design for loads from roof, attic, second story exteriorconcrete wall and second floor, or in the case of a onestory house, design for loads from roof, attic, first storyexterior concrete wall and first floor
5. Design for loads from roof, attic, first and second storyexterior concrete walls and first and second floor
The following design assumptions were used in analyzing thelintels in load-bearing walls:
1. Lintels have fixed end restraints since the walls and lintelsare cast monolithically. The negative moment at thesupport (wl2/12) is the governing moment.
2. In the case of waffle-grid and screen-grid walls, a verticalcore occurs at each end of the lintel for adequatebearing.
3. Lateral restraint (out-of-plane) is provided for the lintel bythe floor or roof system above.
4. Roof slopes range from 0:12 (i.e., flat) to 12:12.
5. Deflection criteria is the clear span of the lintel, ininches, divided by 240, or 1⁄2-inch (13 mm), whichever issmaller. The latter controls for clear spans greater than10 feet (3 m).
6. Roof-ceilings, roofs, and attics span the full width of thehouse (i.e., no interior load-bearing walls or beams). Twoclear spans are covered: 40 feet (12.2 m) and 32 feet(9.8 m).
7. Floor clear spans of 32 feet (9.8 m) and 24 feet (7.3 m)are covered.
8. Roof snow loads were calculated by multiplying theground snow load by 0.77. Therefore, the roof snowload was taken as P = 0.77Pg, where Pg is the groundsnow load in pounds per square foot.
9. Shear reinforcement in the form of No. 3 stirrups isprovided based on ACI 318 [C7.1] and lintel test results;refer to Lintel Testing for Reduced Shear Reinforcementin Insulating Concrete Form Systems [C7.3] and Testingand Design of Lintels Using Insulating Concrete Forms[C7.4].
10. In designing waffle-grid lintels for flexure, an I-beamcross-section was assumed which consisted of 2 flangesof concrete connected by the web. The overall depth, D,was the out-to-out dimension of the flanges. For 6-inch(152 mm) waffle-grid forms, the width and thickness (inthe vertical direction) of each flange was 5 inches (127mm) by 3 inches (76 mm), respectively. For 8-inch (203
mm) waffle-grid forms, the width and thickness (in thevertical direction) of each flange was 7 inches (178 mm)by 3 inches (76 mm), respectively. The web thicknessused to compute the moment of inertia and sectionmodulus was 2 inches (51 mm) since this is the minimumthickness permitted by Table 2.1. See item 12 below.
11. In designing screen-grid lintels for flexure, an I-beamcross-section was assumed which consisted of 2 flangesof concrete connected by an imaginary web. The overalldepth, D, was the out-to-out dimension of the flanges.For the 6-inch (152 mm) screen-grid form, the width andthickness (in the vertical direction) of each flange was 5inches (127 mm) by 2.5 inches (64 mm), respectively. Seeitem 12 below.
12. For waffle- and screen-grid lintels, design shear strengthwas based an effective web thicknesses of 2.6 inches (66mm) and 2.2 inches (56 mm), respectively. These values,which are based on recommendations contained inTesting and Design of Lintels Using Insulating ConcreteForms [C7.4], give some credit to the flanges for theirrole in resisting shear stresses that is not accounted for inthe provisions of ACI 318 [C7.1].
All snow, live and dead loads from the roof, attic, floor(s),wall above, and lintel itself were taken into account in thecalculations using the ACI 318 [C7.1] and ASCE 7 [C7.2]load combination
U = 1.2D + 1.6L + 0.5S or U = 1.2D +0.5L + 1.6S,whichever governed.
For lintels in flat walls, the dead load of the concrete wallsupported by the lintel and the lintel itself, was based onthicknesses of 4, 6, 8 and 10 inches (102, 152, 203 and 254mm). On the other hand, design strength (capacity) wasbased on lintel thicknesses of 3.5, 5.5, 7.5 and 9.5 inches(89, 140, 191 and 241 mm), respectively. This approach willprovide adequate strength for lintels regardless of whetherthe forms used are 1⁄2-inch (13 mm) less than the statednominal thickness, the nominal thickness (4, 6, 8 or 10inches (102, 152, 203 or 254 mm)), or 1⁄4-inch (6 mm) morethan the stated nominal thickness. See Table 2.1 fortolerances permitted for flat walls. For lintels in waffle- andscreen-grid walls, the dead load of the concrete wallsupported by the lintel and the lintel itself was based on themaximum wall weight shown in Table 2.1.
Deflection limits are established primarily with regard toserviceability concerns. The intent is to prevent excessivedeflection that may result in cracking of finishes. Windowsand doors are also sensitive to damage caused by excessive
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C-30
lintel deflection; therefore, a conservative deflection limit ofL /480 for service dead loads and sustained live loads is oftensuggested. This limit is very conservative where the installa-tion of the window and door components is properlydetailed. Accounting for the conservative lintel load analysisdiscussed above, L /240, or 1⁄2-inch, whichever is smaller wasused as the deflection criteria. The following unfactored loadcombinations were used to evaluate deflections:
U = D + L + 0.31S and U = D + 0.31L + S.The lintel section was assumed cracked and the effectivemoment of inertia, Ie, according to Equation 9-8 of ACI 318[C7.1] was used to compute defection, except in the case ofscreen-grid lintels where Ie or 0.15Ig, whichever is smallerwas used. Deflections rarely governed the design. Designmethodologies outlined in the research report entitledTesting and Design of Lintels Using Insulating ConcreteForms [C7.4] were also used.
Because the maximum allowable clear span of a lintel with asingle No. 4 or No. 5 bar in the top and bottom will notaccommodate larger openings, such as for a double-cargarage door, two-bar options have been provided. Sincemost of the longer spans in the tables require two bars atthe top and bottom of the lintel, in addition to stirrups,special attention needs to be given to the consolidation ofthe concrete. A mechanical vibrator is highly recommendedin this situation.
Where stirrups are required in a lintel with a single bar in thetop and bottom, they are normally fabricated like the letter“c” or “s” with 135-degree standard hooks as shown inFigure 2.6 and installed as shown in Figures 7.3 through 7.5.Where two bars are required in the top and bottom of thelintel, stirrups must be fabricated with 90- or 135-degreestandard hooks as shown in Figure 2.6 and installed asshown in Figures 7.3 and 7.4 unless the bars are bundled.
C7.2.2 Lintels Designed for Uplift LoadingConditions
As evidenced by some cases of significant uplift forces inTable 7.1A, lintels may be subjected to reversed loadingconditions in high-wind events. Since lintels are designed forgravity loading conditions assuming fixity at the ends (seeC7.2.1), reinforcement is required in the top and bottom.Therefore, in many cases lintels designed for gravity loadingconditions have design strengths that are adequate forsustaining the uplift forces to which they will be subjected;however, this may not always be the case. Therefore, a lintelmust be designed to sustain the gravity loading condition
and uplift loading condition, and constructed to withstandthe more severe of the two loading conditions.
Lintel designs for gravity load-bearing conditions in Tables7.3 through 7.16 were checked and it was determined thatlintels at the top of a concrete wall that support a roof havedesign strengths sufficient to resist at least 600 plf (8.76kN/m) of factored wind uplift force. Since uplift forces canexceed 600 plf (8.76 kN/m) as indicated in Table 7.1A, linteluplift designs are provided in Tables 7.19 – 7.25. Linteldesigns in these tables are based on the same assumptionsused to prepare the tables for gravity loading conditions (seeC7.2.1), with the following exceptions.
1. Design for roof uplift is based on the ACI 318 [C7.1] andASCE 7 [C7.2] load combination U = 0.9D + 1.6W, sincethe wind uplift force counteracts the dead load.
2. Roof-ceiling spans considered are based on building end -wall lengths shown in Table 7.1A.
3. Dead load of floors, if any, is neglected.
4. For lintels in flat walls, dead loads and design strengthsare based on thicknesses of 3.5 (89), 5.5 (140), 7.5 (191)and 9.5 inches (241 mm) for 4- (102 mm), 6- (152), 8-(203) and 10-inch (254 mm) nominal walls, respectively.No dead load is included for any exterior or interior wallfinishes that may be applied to the lintel.
5. Critical section for shear is assumed to occur at the faceof the support, instead of at distance d from the face ofthe support as was assumed for lintels subject to gravityload-bearing conditions (see C7.2.1). This accounts forthe permissible clear span of a lintel without stirrupsbeing equal to the center distance, A, where stirrups arenot required in lintels with stirrups.
Where a lintel subject to uplift forces from the roof supportsa light framed second story above, no deduction for thedead load of the light framed wall above is to be taken sinceit is insignificant. Where a lintel located in the second storybelow the roof may be subjected to uplift from the roof, andthe exterior wall in the story above the lintel is of concreteconstruction, the factored dead load of the supported wallindicated in Section 7.2.2 is allowed to be deducted fromthe factored roof uplift force from Table 7.1A. The factoreddead load permitted to be deducted is based on thefollowing assumptions:
1. floor to ceiling wall height – 8 feet (2.4 m)
2. floor thickness (to determine dead load of supportedwall) – 16 inches (406 mm)
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Appendix C – Commentaries
3. dead load of concrete wall (based on wall within a wallgroup having the lowest weight – where a flat wall isincluded in a wall group, the thickness used to calculatethe dead load is one-half inch (13 mm) less than thenominal thickness – see Table 2.1)
4. dead load of windows and doors in openings – 4 psf(0.19 kN/m2)
5. percent of openings in wall (based on portion of wallbetween floor and ceiling) – 15%
6. dead load factor – 0.9
Just because the provisions require that a lintel be designedfor uplift, it does not necessarily mean that the uplift condi-tion will control the design of the lintel.
C7.2.3 Bundled Bars in Lintels
Section 7.6.6 of ACI 318 [C7.1] permits bars to be bundledif provisions applicable to the bundled bars are followed. Thenumber of bars being bundled is limited to two to increasethe likelihood that the bundle will be properly encased byconcrete, and to avoid having to increase developmentlengths required by Section 12.4.1 of ACI 318 for 3 or 4 barsin a bundle. The limitation on bar size in item 1 is based onthe maximum bar size shown in the lintel tables and isconsistent with residential construction practices. Therequirement in item 2 that the wall be thick enough wherehorizontally oriented bundled bars are used to provide aminimum of 3 inches of clear space beside the bars is basedon the use of 2 No. 4 bars bundled horizontally in a 4-inchwall. This requirement is to assure that the bundle isproperly encased in concrete and to facilitate getting con -crete to portions of the lintel below the bundle. The require-ment in item 3 that hook extensions in vertically orientedbundles be separated by at least one inch is based on recom-mendations in Commentary Section R7.6.6 of ACI 318. Thelimitation in item 4 on location of lap splices of bundled barsis to make sure that congestion due to the laps will notoccur in the critical stress areas of the lintel. Item 5 is consis-tent with ACI 318 requirements.
C7.2.4 Lintels Without Stirrups Designed forNon Load-Bearing Conditions
Lintels in non load-bearing walls are horizontal membersused to transfer wall dead loads from above aroundopenings. Lintels are divided into two categories as follows:
1. lintels at the top of the wall in a one-story building or thesecond story of a two-story building where the gable
portion of the endwall is light-framed construction(supporting light-framed gable); and
2. lintels in concrete wall, including the gable (supportingconcrete wall).
The following design assumptions were made in analyzingthe lintels in non-load-bearing walls:
1. Lintels have fixed end restraints since the walls and lintelsare cast monolithically. The negative moment at thesupport (wl2/12) is the governing moment.
2. In the case of waffle-grid and screen-grid walls, a verticalcore occurs at each end of the lintel for proper bearing.
3. Lateral restraint (out-of-plane) is provided for the lintel bythe floor or roof system above.
4. Allowable deflection criteria is the clear span of the lintel,in inches, divided by 240, or 1⁄2-inch (13 mm), whicheveris smaller.
5. Lintels support only dead loads from the wall above.
Loads experienced by the lintel are uniform loads and do nottake into account any arching action, except as noted below,that might occur above the lintel within a height equal tothe lintel clear span because opening locations above thelintel cannot be determined for all cases. For lintels in con -crete walls, arching action was considered and criterialimiting the use of the condition have been placed in a noteto the tables so arching action can be relied upon. For lintelssupporting a light-framed wall, the wall was assumed tohave a dead load of 10 psf (0.48 kN/m2) and a height of 18feet (5.5 m). Lintel dead load and the dead load of the wallabove were taken into account in the calculations using ACI318 [C7.1] load combination, U = 1.4D.
For lintels in flat walls, the dead load of the concrete wallsupported by the lintel and the lintel itself, was based onthicknesses of 4, 6, 8 and 10 inches (102, 152, 203 and 254mm). On the other hand, required strength was based onlintel thicknesses of 3.5, 5.5, 7.5 and 9.5 inches (89, 140,191 and 241 mm), respectively. This approach will provideadequate strength for lintels regardless of whether the formsused are 1⁄2-inch (13 mm) less than the stated nominal thick-ness, the nominal thickness (4, 6, 8 or 10 inches (102, 152,203 or 254 mm)), or 1⁄4-inch (6 mm) more than the statednominal thickness. For lintels in waffle- and screen-grid walls,the dead load of the concrete wall supported by the linteland the lintel itself was based on the maximum wall weightshown in Table 2.1.
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Deflection limits are established primarily with regard toserviceability concerns. The intent is to prevent excessivedeflection that may result in cracking of finishes. Windowsand doors are also sensitive to damage caused by linteldeflection; therefore, a conservative deflection limit of L /480for service dead loads and sustained live loads is oftensuggested. This limit is very conservative when theinstallation of window and door components is properlydetailed. Accounting for the conservative lintel load analysisdiscussed above, L /240, or 1⁄2-inch, whichever is smaller forfull service dead load was used.
The lintel section is assumed cracked and the effectivemoment of inertia, Ie, according to Equation 9-8 of ACI 318[C7.1] is used to compute defection, except in the case ofscreen-grid lintels where Ie or 0.15Ig, whichever is smallerwas used. Deflections rarely governed the design.
REFERENCES
C7.1 Building Code Requirements for Structural Concrete(ACI 318-05) and Commentary (ACI 318R-05).American Concrete Institute, Farmington Hills,Michigan. 2004.
C7.2 Minimum Design Loads for Buildings and OtherStructures, including Supplement No. 1, ASCE/SEI 7-05.American Society of Civil Engineers, Reston, Virginia.2005.
C7.3 Lintel Testing for Reduced Shear Reinforcement inInsulating Concrete Form Systems. Prepared for theU.S. Department of Housing and Urban Development,Portland Cement Association, and the NationalAssociation of Home Builders by NAHB ResearchCenter, Inc., Upper Marlboro, Maryland. 1998.
C7.4 Testing and Design of Lintels Using Insulating ConcreteForms. Prepared for the U.S. Department of Housingand Urban Development, Portland Cement Association,and the National Association of Home Builders by theNAHB Research Center, Inc., Upper Marlboro,Maryland. 2000.
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D-1
Appendix DDesign Example
Before starting the design process, the building parameters,and site and environmental parameters must first be deter-mined to ascertain if the proposed building is within thescope of the Standard in accordance with Section 1. If thebuilding is found to be within the scope of the Standard,design can begin but it must be carried out in a logicalsequence so that design features determined at the begin-ning (e.g., wall type and thickness) are not found to beimpractical or inadequate later in the process. Since most ofthis Standard deals with the design of various aspects ofexterior concrete walls, which in turn are influenced by thetype of wall (i.e., flat, waffle- or screen-grid) and nominalthickness, the first step should be to select a preliminary typeof wall and nominal thickness that will not have to be revisedlater. The following is a suggested approach that, if followed,will result in an efficient design process.
If the designer wishes to use the prescriptive details inSection 6 (Figures 6.3 through 6.14) for the connectionsbetween the concrete walls and floors and roof, a wall typeand thickness needs to be selected that will permit the useof the appropriate details. Once the wall type and thicknesshave been selected, determination of the remaining designfeatures can proceed. The examples that follow utilize thisapproach.
One cautionary note needs to be mentioned. As indicatedabove, this Standard recognizes three wall types; flat, waffle-and screen-grid. Within each wall type there may be morethan one nominal thickness. Design solutions for four (4)nominal thicknesses of flat walls are included: 4-, 6-, 8- and10-inch. Two nominal thicknesses of waffle-grid walls arerecognized: 6- and 8-inch. Screen-grid walls are limited to 6-inch nominal. For additional dimensional information onthese walls, see Table 2.1 and Figures 2.1 through 2.3. Theuser needs to be aware that all of these wall types and thick-
nesses are permitted to be used, subject to the design limita-tions in the Standard, with one exception. Flat walls with anominal thickness of 4 inches are not permitted for multipledwellings assigned to Seismic Design Category C, and allbuildings assigned to Seismic Design Category D0, D1 or D2.Because of this limitation and other seismic provisions, itrecommended that for multiple dwellings assigned toSeismic Design Category C, and all buildings assigned toSeismic Design Category D0, D1 or D2, seismic design shouldbe performed first.
Design the single family dwelling shown below in accor-dance with this Standard. Site and environmental designparameters are based on the International Residential Code.
The only significant difference in site and environmentalfactors, and building parameters between the wind designexample and the seismic design example is the SeismicDesign Category. In the wind design example, the buildingdoes not need to be designed for seismic forces since it isassigned to Seismic Design Category A. In the seismic designexample, seismic design is required since the building isassigned to Seismic Design Category D1. Since the basicwind speed and exposure categories are the same in the twoexamples, reinforcement and other design features requiredfor wind design are applicable to the seismic design example.However, in the seismic design example, the building willneed to be checked to see if any reinforcement or otherdesign features need to be changed in order to comply withthe seismic provisions of the Standard. Step numbers used inthe two examples correspond to each other. In order tomaintain step-number consistency, in some cases steps in theexamples have been noted as “intentionally left blank”which indicates that design feature addressed in oneexample do not apply to the other.
This appendix is provided for information purposes only and is not a part of this Standard.
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D-2
Prescriptive Design of Exterior Concrete Walls for One- and Two-Family Dwellings
Plan – First Story
NOTE: Assume same exterior wall opening layout for secondstory as shown for first story, except the doors becomewindow openings.
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Appendix D – Design Example
D-3
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D-4
Site and Environmental Parameters
Location: Sebastian, Florida
Base wind speed: 130 mph (58 m/s)
Wind exposure category: C
Seismic Design Category: A
Ground snow load: 0
Assumed load-bearing value of soil: 2,000 psf
Building Parameters
Interior wall, floor and roof framing: cold-formed steel
Number of stories: 2
Foundation type: Monolithic footing and slab-on-ground
Floor-to-ceiling clear height: first story, 9 feet; second story, 8 feet
Floor joist spacing and span: 19.2 inches and ≈ 18 feet maximumFloor joists connections to wall: steel track bolted to side of wall
Roof and ceiling framing spacing and span: 24 inches and ≈ 30 feetRoof type: Gable with ridge oriented east-west
Roof truss connections to wall: Bearing on top of wall
Roof live load: 20 psf (use 30 psf ground snow load)
Roof slope: 7 in 12 (30 degrees)
Roof overhang: 2 feet all roof edges
Mean roof height: ≈ 25 feet (see step 4b for calculation)Exterior wall covering: cement stucco (installed weight ≈ 11 psf)Building aspect ratio: L/W = 60/30 = 2
Other: see floor plan
Material Properties
Specified compressive strength of concrete, f ’c = 2,500 psi
Specified yield strength of steel reinforcement, fy = 60,000 psi (Grade 60)
Prior to beginning the design, the building parameters must be compared to the limitations of Section 1.2 to see if thebuilding is within the scope of the Standard. Upon checking, this building is determined to be within the scope.
Wind Design
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D-5
Appendix D – Design Example
Site/Environmental Parameters
Same as Wind Design example, except as follows:
Location: Charleston, South Carolina
Seismic Design Category: D1Ground snow load: 5 psf
Building Parameters
Same as Wind Design Example, except as follows:
Exterior wall covering: 5⁄16-inch fiber-cement siding (installed weight less than 3 psf)
Material Properties
Specified compressive strength of concrete, f ’c = 3,000 psi (see Section 2.2.5)
Specified yield strength of steel reinforcement, fy = 60,000 psi (Grade 60)
Prior to beginning the design, the building parameters must be compared to the limitations of Section 1.2.2 to see if thebuilding is “regular.” Upon checking, this building is determined to be regular.
Seismic Design
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Step 1 – Determine preliminary wall type and thickness based on prescriptiveconnection details that are applicable.
a. Use detail in Figure 6.7 for connecting cold-formed steel floor joist spanning perpendicular to wall (i.e.,wall lines 1 and 2). Since floor joists will be spaced at 19.2 inches on center, anchor bolts and tensionties should generally be spaced at some whole-number multiple of 19.2 inches. In this case, use of a 6-inch flat wall is permitted where the basic wind speed is 130 mph, exposure C. This will permit anchorbolts and tension ties to be spaced a maximum of 19.2 and 38.4 inches on center, respectively.
Use 6-inch flat wall as the preliminary wall type and thickness. Wall Group #2 includes 6-inch flatwalls.
ReferenceSection (§),Table (T), andFigure (F)
§ 6
§ 6.4
F 6.7
b. Use detail in Figure 6.8 for connecting cold-formed steel floor joists spanning parallel to wall (i.e., walllines A and B). Preliminary selection in step 1a is OK with same anchor bolt and tension tie spacing.
§ 6.4
F 6.8
c. Use detail in Figure 6.13 for connecting cold-formed steel roof/ceiling framing spanning perpendicular towall (i.e., wall lines 1 and 2). Since roof framing will be spaced at 24 inches on center, use of a 6-inch flatwall preliminarily selected in step 1a is permitted where the basic wind speed is 130 mph, exposure C. Thiswill require that anchor bolts and tension ties be spaced a maximum of 12 and 24 inches on center,respectively.
§ 6.5
F 6.13
d. Use detail in Figure 6.14 for connecting cold-formed steel roof/ceiling framing spanning parallel to wall(i.e., wall lines A and B). Preliminary selection in step 1a above is OK with same anchor bolt and tension tiespacing as required in step 1c above. Observe from Figure 6.14 table that if the top portion of the wall isincreased in thickness to 8 inches (see cross-hatched area in Figure 6.14), anchor bolts and tension ties canbe spaced 19.2 inches and 38.4 inches, respectively, provided the diameter of the anchor bolt is increasedfrom 1⁄2-inch to 5⁄8-inch.
WARNING: Note 7 of the table that accompanies Figure 6.14 indicates that 5⁄8-inch bolts are not permittedfor buildings assigned to Seismic Design Category C, D0, D1 or D2.
§ 6.5
F 6.14
e. As a preliminary wall thickness and type, use a 6-inch flat wall.
Use 6-inch flat wall
Step 2 – Determine vertical reinforcement required in walls to resist out-of-plane lateral wind forces.
HINT: For a 2-story building where the exterior walls of both stories are of concrete, and the second floorframing is attached to the wall via a wood ledger or steel track (side bearing), the design should proceed byselecting the vertical wall reinforcement for the first story bearing walls first. This is due to the fact that fora given bar size and grade of steel, first story bearing walls will generally require more reinforcement (i.e.,closer bar spacing) since the second floor framing is attached to the side of the wall.
Wind Design
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Appendix D – Design Example
Step 1 – Determine preliminary wall type and thickness based on prescriptiveconnection details that are applicable.
a. Using Figure 6.7 for floor joists spanning perpendicular to the wall, from step 1a for wind design it wasdecided to use anchor bolts and tension ties spaced at 19.2 and 38.4 inches on center, respectively. Forseismic design for SDC D1, these spacings are not permitted. However, if the spacing of tension ties isreduced to 19.2 inches, a 6-inch flat wall is permitted, so this will continue to be the preliminary wallthickness.
Use 6-inch flat wall as the preliminary wall type and thickness. Wall Group #2 includes 6-inch flatwalls.
ReferenceSection (§),Table (T), andFigure (F)
§ 6.4
F 6.7
b. Using Figure 6.8 for floor joists spanning parallel to wall, the 6-inch flat wall preliminarily selected is OKwith the same anchor bolt and tension tie spacing as in step 1a above.
§ 6.4
F 6.8
c. Using Figure 6.13 for roof/ceiling framing spanning perpendicular to wall, from step 1c for wind design itwas decided to use anchor bolts and tension ties spaced at 12 and 24 inches on center, respectively. Forseismic design for SDC D1, these spacings are not permitted for a 6-inch flat wall. However, if the spacingof the tension ties is reduced to 12 inches and the portion of the wall indicated by cross-hatching in Figure6.13 is increased to 8 inches, Note 6 to the table will permit a flat wall with a nominal thickness of 6inches, so this will continue to be the preliminary wall thickness.
NOTE: In this detail, the framing members are used to transfer the force from the top of the wall into theceiling and/or roof diaphragm. Since the roof framing members are spaced 24 inches on center, theconnection detailed in Figure 6.13 will need to be redesigned to distribute the force from the anchor boltslocated between the framing members into the framing members since tension ties must be located nomore than 12 inches on center. Forces in the applicable tables in Appendix A or B can be used to: 1) selecta proprietary connector (See Section 6.5, Item 3), or 2) the connection will need to be designed by aregister design professional (see Section 6.5, item 4). Alternatively, connections may be designed by aregistered design professional utilizing the design loads and forces calculated in accordance with ASCE 7,and the resistances provided by concrete in accordance with ACI 318, and cold-formed steel in accordancewith AISI/S100 (see Section 6.5, item 5).
HINT: Some insulating concrete form manufacturers make a special form unit that permits the thickness ofthe wall to be increased by approximately 2 inches at the top portion of the wall.
§ 6.5
F 6.13
d. Using Figure 6.14 for roof/ceiling framing spanning parallel to wall, the preliminary selection in step 1aabove of 6-inch flat wall is OK for anchor bolt and tension ties spaced at 16 inches on center, provided theportion of the wall indicated by cross-hatching in Figure 6.14 is increased to 8 inches in accordance withNote 6 to the table that accompanies the figure.
NOTE: For connections to walls that are parallel to framing members, tension ties do not connect toframing members; therefore, the largest possible tension tie spacing permitted by the table for the wallthickness should be used. Although tension ties do not connect to framing members, they must beattached to blocking installed between framing members.
§ 6.5
F 6.14
e. As a preliminary wall thickness and type, use a 6-inch flat wall.
Use 6-inch flat wall
Step 2 – Determine vertical reinforcement required in walls to resist out-of-plane lateral seismic forces.
HINT: For a 2-story building where the exterior walls of both stories are of concrete, and the second floorframing is attached to the wall via a wood ledger or steel track (side bearing), the design should proceed byselecting the vertical wall reinforcement for the first story bearing wall first. This is due to the fact that for agiven bar size and grade of steel, first story bearing walls will generally require more reinforcement (i.e.,closer bar spacing) since the second floor framing is attached to the side of the wall.
Seismic Design
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a. Determine vertical reinforcement for first story bearing walls (wall lines 1 and 2):
Since the first story wall will be supporting the second floor joists spanning perpendicular to the wall by atrack bolted to the side of the wall (side bearing), in Table 4.1 under the columns for 6-inch wall, use thecolumn labeled “side,” and in the row for 130 mph, exposure C, 9-foot maximum unsupported wallheight, determine that No. 5 bars at 38 inches on center are required. Per Note 8 to Table 4.1, bars mustbe Grade 60.
As an alternate to No. 5 Grade 60 bars at 38 inches on center, Note 8 to Table 4.1 permits bars of adifferent grade of steel and/or size to be used provided an equivalent area of reinforcement is provided inaccordance with Section 2.5.7 and Table 2.3. In this case, the contractor has indicated that he prefers touse No. 4 Grade 60 bars if possible. Table 2.3 permits No. 4 Grade 60 bars at 25 inches on center.Numerous other combinations of bar size No. and/or grade of steel could be used to satisfy therequirements of Table 4.1 for No. 5 Grade 60 bars at 38 inches on center.
Use No. 4 Grade 60 bars at 24 inches on center.
§ 4.1.1
§ 4.1.2
T 4.1,
Notes 8 &10
T 2.3
b. Determine vertical reinforcement for first story non-bearing walls (wall lines A and B):
Per note 10 of Table 4.1, under the columns for 6-inch wall, use the column labeled “top,” and in the rowfor 130 mph, exposure C, 9-foot maximum unsupported wall height, determine that No. 5 Grade 60 barsat 43 inches on center are required. As an alternate to No. 5 bars, Table 2.3 permits use of No. 4 Grade 60bars at 28 inches on center.
Use No. 4 Grade 60 bars at 24 inches on center.
§ 4.1.1
§ 4.1.2
T 4.1,
Notes 8 &10
c. Determine vertical reinforcement for second story bearing walls (wall lines 1 and 2):
Since a 6-inch flat wall was tentatively selected in Step 1, use Table 4.1 for flat walls to determine therequired bar size and maximum spacing of vertical reinforcing bars. Since the second story wall will besupporting the roof/ceiling framing spanning perpendicular to the wall bearing on top of the wall (topbearing), under the columns for 6-inch wall, use the column labeled “top,” and in the row for 130 mph,exposure C, 8-foot maximum unsupported wall height, determine that No. 4 bars at 48 inches on centerare required. Per Note 7 to Table 4.1, bars may be either Grade 40 or 60. This will permit every bar in thesecond story wall (i.e., bars spaced at 48 inches on center) to be lap-spliced with every other bar in thefirst story wall (i.e., bars spaced at 24 inches on center). In order to avoid confusion during construction,Grade 60 bars will be used throughout.
§ 4.1.1
§ 4.1.2
T 4.1,Notes 7 & 10
d. Determine vertical reinforcement for second story non-bearing walls (wall lines A and B):
Per note 10 of Table 4.1, under the columns for 6-inch wall, use the column labeled “top,” and in the rowfor 130 mph, exposure C, 8-foot maximum unsupported wall height, determine that No. 4 bars at 48inches on center are required. As in Step 2c above, either Grade 40 or 60 bars may be used; however,Grade 60 will be used.
§ 4.1.1§ 4.1.2T 4.1,Notes 7 & 10
e. Summary of vertical wall reinforcement requirements.
First story – No. 4@24" on center (Grade 60)
Second story – No. 4@48" on center (Grade 60)
Step 3 – Determine horizontal reinforcement required in walls.
Section 4.1.2 requires that walls have not less than 4 – No. 4 Grade 40 bars placed as follows: one barwithin 12 inches of the top of the wall, one bar within 12 inches of the floor, and one bar each at approxi-mately one-third and two-thirds the wall height.
Horizontal wall reinforcement: use 4 – No. 4 Grade 60 bars per story.
§ 4.1.2
Step 4 – Determine length of solid wall required and vertical reinforcement required in each end of solid wallsegments to resist in-plane lateral wind forces. For this example, wall line B of the first story will be illustratedsince it is the wall with the least amount of solid wall length.
Wind Design
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Appendix D – Design Example
a. Determine vertical reinforcement for first story bearing walls (wall lines 1 and 2):
From step 2a for wind design, it was decided to use No. 4 Grade 60 bars at 24 inches on center for thefirst story walls. However, Section 4.1.3 requires that for buildings assigned to Seismic Design Category D1,vertical reinforcement must not be less than No. 5 Grade 60 bars at no more than 18 inches on center, orNo. 4 Grade 60 bars at no more than 12 inches on center. Therefore, the vertical reinforcement is prelimi-narily selected as No. 4 Grade 60 bars at 12 inches on center.
NOTE: The Standard does not have tables that give the size and spacing of vertical reinforcement requiredto resist out-of-plane seismic forces. This is due to the fact that the minimum prescriptive reinforcementprescribed in Section 4.1.3 is usually significantly more than required by analysis for this purpose, with theexception of some stem walls designed continuous with above-grade walls without lateral support at theslab-on-ground (see Table 4.4).
§ 4.1.1
§ 4.1.3
b. Determine vertical reinforcement for first story non-bearing walls (wall lines A and B):
Same as step 2a above.
§ 4.1.1
§ 4.1.3
c. Determine vertical reinforcement for second story bearing walls (wall lines 1 and 2):
From step 2c for wind design, it was decided to use No. 4 Grade 60 bars at 48 inches on center for thesecond story walls. However, Section 4.1.3 requires that for buildings assigned to Seismic Design CategoryD1, vertical reinforcement must not be less than No. 5 Grade 60 bars at not more than 18 inches oncenter, or No. 4 Grade 60 bars at not more than 12 inches on center. Therefore, the vertical reinforcementis preliminarily selected as No. 4 Grade 60 bars at 12 inches on center.
§ 4.1.1
§ 4.1.3
d. Determine vertical reinforcement for second story non-bearing walls (wall lines A and B):
Same as step 2c above.
§ 5.1.2
T 5.5B,incl. Note8
e. Summary of vertical wall reinforcement requirements.
First story – No. 4@12" on center (Grade 60)
Second story – No. 4@12" on center (Grade 60)
Step 3 – Determine horizontal reinforcement required in walls.
For wind design, it was decided to use 4 – No. 4 horizontal bars in each story. However, Section 4.1.3 re-quires that for buildings assigned to Seismic Design Category D1, horizontal reinforcement must not be lessthan No. 5 Grade 60 bars at not more than 18 inches on center, or No. 4 Grade 60 bars at not more than 12inches on center. This reinforcement will also serve as horizontal shear reinforcement required by Table 5.4A,note 4. Therefore, the maximum spacing of the reinforcement must comply with Section 5.2.2.1.
Horizontal wall reinforcement: use No. 4 Grade 60 bars at 12 inches on center.
§ 4.1.3
§ 5.2.2.1
T 5.4A,Note 4
Step 4 – Determine length of solid wall required and vertical reinforcement required in each end of solid wallsegments to resist in-plane lateral seismic forces. For this example, wall line B of the first story will beillustrated since it is the wall with the least amount of solid wall length.
Seismic Design
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a. Since the controlling condition for wall line B is for wind blowing perpendicular to the ridge, use Table5.1B (first story of two-story) to determine the unadjusted length of solid wall, TL, required. Under thecolumn for a basic wind speed of 130 mph, exposure C, and the row for building sidewall length of 60feet, endwall length of 30 feet, and roof slope of 7 in 12, the unadjusted length of solid wall, TL, requiredis 49.55 feet. Per Note 2 of the table, determine if 49.55 feet is less than the “minimum” value in theright-most column of the table. Since the “minimum” value is 15.18 feet, 49.55 feet controls for TL.
§ 5.1.1
T 5.1B,incl. Note2
b. The TL values in Tables 5.1A, B and C were determined based on a wind pressure assuming a mean roofheight of 35 feet. If the mean roof height of the building being designed is less than 35 feet, TL, exceptwhen the “minimum” value governs, is permitted to be reduced by the reduction factor for mean roofheight, R5.2, from Table 5.2. The mean roof height is determined as follows:
assumed height of top of slab-on-ground above adjacent ground level 1 foot
floor-to-ceiling height of first and second stories (9 + 8 = 17) 17 feet
assumed thickness of second floor framing system 1 foot
assumed height from top of second story wall to top of roof sheathingmeasured at the exterior surface of wall 1.75 feet
one-half of height of roof ((7/12) x 15)/2 = 4.375 4.375 feet
TOTAL = mean roof height 25.125 feetUse 25 feet for mean roof height
In Table 5.2 under column for exposure C and in row for mean roof height of 25 feet, determine that thereduction factor for mean roof height, R5.2, is 0.93.
NOTE: The Standard does not require that the reduction factor, R5.2, be utilized. The user may wish toavoid the complications of computing the mean roof height, in which case the value of 1 will be used inEqs. 5-1 and 5-2.
§ 5.1.1
T 5.2
Eq. 5-1
c. The TL values in Tables 5.1A, B and C were determined based on the assumption that the total floor-to-ceiling wall height of the first and second stories is 20 feet. If the actual total floor-to-ceiling wall height ofboth stories is less than 20 feet, TL is permitted to be reduced by the reduction factor for floor-to-ceilingheight, R5.3, from Table 5.3. In the case of the example, the total floor-to-ceiling height of both stories is17 feet (9 + 8 = 17). A review of Table 5.3 will reveal that in the case of the example, double interpolationwill be required since reduction factors for neither the combined wall height of 17 feet, nor endwalllength of 30 feet are tabulated.
First, determine by interpolation the factor for an endwall length of 15 feet, and a total floor-to-ceilingheight of 17 feet as follows:
17 – 16x (1 – 0.86) + 0.86 = 0.895
20 – 16
Second, determine by interpolation the factor for an endwall length of 60 feet, and a total floor-to-ceilingheight of 17 feet as follows:
17 – 16x (1 – 0.91) + 0.91 = 0.9325
20 – 16
Finally, with the reduction factors for endwall lengths of 15 and 60 feet, for a total floor-to-ceiling wallheight of 17 feet, a third interpolation is performed to determine the reduction factor for an endwalllength of 30 feet and a wall height of 17 feet as follows:
30 – 15x (0.9325 – 0.895) + 0.895 = 0.9075
60 – 15
Therefore, the reduction factor for floor-to-ceiling wall height, R5.3, is 0.9075.
§ 5.1.1
T 5.3
Wind Design
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Appendix D – Design Example
a. Use Table 5.5B (first story of two-story) to determine the unadjusted length of solid wall, TL, required.Since the area of the building within the exterior walls is 1800 square feet, under the column for 2,000square feet, and the row for Seismic Design Category D1 for ground snow load of less than 40 psf, andwall group 2, which includes the 6-inch flat wall, determine that the required unadjusted length of solidwall, TL, is 35.92 feet. Since TL is significantly greater than the actual length of solid wall, determine TLfor 1,800 square feet by interpolation as permitted by Table 5.5B note 8 as follows:
(1800–1500)(35.92–30.09) + 30.09 = 33.59 feet
(2000–1500)
§ 5.1.2
T 5.5B,incl. Note8
b. The TL values in Tables 5.5A, B and C were determined based on the assumption that the total floor-to-ceiling wall height of the first and second stories is 20 feet. If the actual total floor-to-ceiling wall height ofboth stories is less than 20 feet, TL is permitted to be reduced by the reduction factor for floor-to-ceilingheight, R5.6, from Table 5.6A. In the case of the example, the total floor-to-ceiling height of both stories is17 feet (9 + 8 = 17). In the lower portion of Table 5.6A for “first story of two-story,” under the column forarea of building of 2,000 square feet, and row for 8' top story and 9' bottom story for wall group 2, deter-mine that the reduction factor is 0.90. Since the reduction factor for 1,500 square feet is only 0.01 lessthan the value for 2,000, a very small further reduction will be realized by interpolating; therefore, use0.90.
NOTE: The Standard does not require that the reduction factor, R5.6, be utilized. The user may wish toavoid the complications of computing the factor, in which case the value of 1 will be used in Eqs. 5-3and 5-4.
§ 5.1.2
T 5.6A
c. The TL values in Tables 5.5A, B and C were determined based on the assumption that the installed weightof the exterior wall covering is 11 psf. Since the building’s exterior wall covering is 5⁄16-inch fiber-cementsiding, which has an installed weight of 3 psf or less, TL is permitted to be reduced by the reduction factorfor exterior wall covering weight, R5.7, from Table 5.7. In the middle portion of Table 5.7 for “first story oftwo-story” under the column for area of building of 2,000 square feet, and row for wall group 2,determine that the reduction factor is 0.93. Since the reduction factor for 1,500 square feet is also 0.93,no advantage can be taken for the fact that the actual building area is 1,800 square feet.
§ 5.1.2
T 5.7
Seismic Design
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NOTE: The Standard does not require that the reduction factor, R5.3, be utilized. The user may wish toavoid the complications of computing the factor, in which case the value of 1 will be used in Eqs. 5-1and 5-2.
d. This step intentionally left blank.
e. Using the right side of Eq. 5-1, determine the unadjusted length of solid wall required, TL, reduced by thereduction factors R5.2 and R5.3 as follows:
R5.2 x R5.3 x TL = 0.93 x 0.9075 x 49.55 = 41.82 feet
§ 5.1.1
Eq. 5-1
f. Determine the total length of solid wall segments in wall line B that qualify for use. For buildings assignedto Seismic Design Category A, only segments equal to or greater than 24 inches in length are permitted tobe used, and only 2 segments with a length of less than 48 inches can be considered.
Total length of qualifying solid wall segments A + B + C + D = 4 + 8.5 + 4.5 + 3 = 20 feet
§ 5.2
§ 5.2.1.1
g. Since the reduced length of solid wall required is 41.82 feet (see step 4e above), which is greater than the20 feet of solid wall available (see step 4f above), it is necessary to use Eq. 5-2 to determine an averageadjustment factor, Fa, to enter Table 5.4A to determine the amount of vertical reinforcement required ateach end of the solid wall segments. Fa is computed as follows:
Fa =R5.2 x R5.3 x TL
=41.82
= 2.09A + B + C + D 20
A review of Table 5.4A for a 6-inch flat wall for a solid wall segment length of 36 inches for 2 – No. 4Grade 60 bars arranged as shown in detail 3 of Figure 5.1 indicates that the segment has a value of F =2.10. Recall that the least length of a qualifying solid wall segment (i.e., segment D) in wall line B is 36";therefore, this is adequate.
In this case, horizontal shear reinforcement is not required; therefore, vertical shear reinforcementcomplying with the maximum spacing of Section 5.2.2.3 is not required.
Use 2 No. 4 Grade 60 bars arranged as indicated in Detail 3 of Figure 5.1 in each end of each solidwall segment.
NOTE: While this amount of reinforcement and the length of solid wall segments will satisfy the require-ments of Table 5.1B, additional reinforcement may be required at the ends of solid wall segments adjacentto openings to satisfy other provisions. See step 6.
§ 5.1.1
§5.2.2.1
Eq. 5-2
T 5.4A
F 5.1
Step 5 – Determine number and size of vertical bars required adjacent to wall openings equal to or greaterthan 2 feet in width. For the example, the widest opening on the second story will be evaluated, which is8 feet.
NOTE: Assume same exterior wall opening layout for second story as shown for first story, except thedoors become window openings.
§ 7.1
a. Determine the factored roof uplift force using Table 7.1A. Since the roof slope is 7 in 12, use the lowerportion of the table for “all portions of wall where roof slope is > 5.6 in 12 (> 25 degrees).” From the rowfor “all” sidewall lengths and endwall length of 30 feet, and under the column for 130 mph, exposure C,the uplift force is 701 plf.
Since the roof has a 2-foot overhang, the value determined above needs to be increased to account forthe additional uplift on the overhang. Enter the lower portion of the table for “additional uplift to beadded per foot of horizontal projection of roof overhang (plf)” and determine that the additional upliftforce is 57 plf. These two uplift values are combined as follows:
701 + (2 x 57) = 701 + 114 = 815 plf
§ 7.1.2
T 7.1A,incl.Note 4
Wind Design
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Appendix D – Design Example
NOTE: The Standard does not require that the reduction factor, R5.7, be utilized. The user may wish toavoid the complications of computing the factor, in which case the value of 1 will be used in Eqs. 5-3and 5-4.
d. The TL values in Tables 5.5A, B and C were determined based on two ground snow load conditions: 1) lessthan 40 psf, in which case no snow load was included in the seismic weight of the building, and 2) 70 psf.Since the actual snow load for this example is 5 psf, no reduction factor for ground snow load, R5.8 (fromTable 5.8), is permitted; therefore, R5.8 equals 1.0.
§ 5.1.2
T 5.8
e. Using the right side of Eq. 5-3, determine the unadjusted length of solid wall required, TL, reduced by thereduction factors R5.6, R5.7 and R5.8 as follows:
R5.6 x R5.7 x R5.8 x TL = 0.90 x 0.93 x 1.0 x 33.59 = 28.11 feet
§ 5.1.2
Eq. 5-3
f. Determine the total length of solid wall segments in wall line B that qualify for use. For buildings assignedto Seismic Design Category D1, only segments equal to or greater than 48 inches in length are permittedto be used.
Total length of qualifying solid wall segments A + B + C = 4 + 8.5 + 4.5 = 17 feet
§ 5.2
§ 5.2.1.3
g. Since the reduced length of solid wall required is 28.11 feet (see step 4e above), which is greater than the17 feet of solid wall available (see step 4f above), it is necessary to use Eq. 5-4 to determine an averageadjustment factor, Fa, to enter Table 5.4A to determine the amount of vertical reinforcement required ateach end of the solid wall segments. Fa is computed as follows:
Fa =R5.6 x R5.8 x R5.8 x TL
=28.11
= 1.65A + B + C 17
At this point it is important to get acquainted with Table 5.4A, including its notes. Since the building isassigned to Seismic Design Category D1, the prescriptive horizontal reinforcement required by Section 4.1.3must be considered horizontal shear reinforcement; therefore. the spacing limitations of Section 5.2.2.1apply. (see Table 5.4A, note 4). A review of Table 5.4A for a 6-inch flat walls for a solid wall segment length of48 inches for 2 – No. 4 Grade 60 bars arranged as shown in detail 3 of Figure 5.1 indicates that the seg-ment has a value of F = 2.18. Recall that the least length of a qualifying solid wall segment (i.e., segment A)in wall line B is 48"; therefore, since Fa required (i.e., 1.65) is less than F provided this is adequate.
Use 2 No. 4 Grade 60 bars arranged as indicated in Detail 3 of Figure 5.1 in each end of each solidwall segment.
NOTE: While this amount of reinforcement and the length of solid wall segments will satisfy therequirements of Table 5.5B, additional reinforcement may be required at the ends of solid wall segmentsadjacent to openings to satisfy other provisions. See step 6.
§ 5.1.2
Eq. 5-4
T 5.4A
F 5.1
Step 5 – Determine number and size of vertical bars required adjacent to wall openings equal to or greaterthan 2 feet in width. For the example, the widest opening on the second story will be evaluated, which is8 feet.
NOTE: Assume same exterior wall opening layout for second story as shown for first story, except thedoors become window openings.
a. This step intentionally left blank.
Seismic Design
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Since the building’s mean roof height is 25 feet (see step 4b), note 4 of Table 7.1A permits the uplift forcedetermined above to be reduced by multiplying by the appropriate factor from Table 5.2, which for expo-sure C is 0.93. Therefore, the reduced factored uplift force is:
815 x 0.93 = 758 plf
b. Using the factored uplift value determined above in step 5a, enter Table 7.1B under the column for afactored roof uplift force of less than or equal to 800 plf and the row for an opening width of 8 feet, findthat 1 No. 4 Grade 40 bar is required on each side of the opening.
Provide 1 – No. 4 Grade 60 bar on each side of opening.
T 7.1B
Step 6 – Determine number, bar size and arrangement of vertical reinforcement for walls. For this example,the vertical reinforcement for the first story, non-loadbearing wall line B will be determined.
a. Vertical reinforcement may be required for one or more of the following purposes:
1. to resist out-of-plane wind forces acting on the wall,
2. Intentionally left blank.
3. additional reinforcement adjacent to an opening to compensate for reinforcement interrupted at anopening,
4. reinforcement at the ends of solid wall segments to resist the moment due to the in-plane wind forces,
5. reinforcement adjacent to an opening to resist wind uplift forces on the roof that are transferred to thelintel above the opening and then to the supports at the ends of the lintel, and
6. vertical shear reinforcement in solid wall segments.
Reinforcement must be the greater of that required for wind or seismic, if seismic design is required.
Vertical reinforcement required for these purposes is summarized below. All reinforcement is Grade 60.
1. From step 2e, vertical reinforcement required in the wall to resist out-of-plane wind forces is No. 4@24inches on center.
2. Intentionally left blank.
3. If vertical reinforcement required to resist calculated out-of-plane wind forces is interrupted at anopening, the amount interrupted needs to be located adjacent to the opening. The amount interruptedshould be as evenly distributed on both sides of the opening as practical, and should be located within12 inches of the edge of the opening. In this case the calculated reinforcement is No. 4@24. Since mostopenings are 42 inches in width, two bars will generally be interrupted. Therefore, place an additionalNo. 4 bar within 12 inches of each edge of each opening.
4. From step 4g, vertical reinforcement required at each end of solid wall segments is 2 No. 4 barsarranged as illustrated in detail No. 3 of Figure 5.1.
5. From step 5b, vertical reinforcement required to resist roof uplift forces on each side of each wallopening equal to or greater than 2 feet in width is one No. 4 bar.
6. Since horizontal shear reinforcement is not required, vertical shear reinforcement is not required (seestep 4g).
Wind Design
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Appendix D – Design Example
b. Section 7.1.2 stipulates that in multiple dwellings assigned to Seismic Design Category C, and all buildingsassigned to Seismic Design Category D0, D1 or D2, not less than 2 No. 4 bars (Grade 60) or one No. 5 bar(Grade 60) shall be provided within 12 inches of each side of all openings equal to or greater than 2 feetin width, but in no event can the amount of reinforcement be less than required for wind uplift. See step5b for wind design.
Provide 2 – No. 4 Grade 60 bars on each side of opening.
§ 7.1.2
Step 6 – If such tables had been provided, the amount of vertical reinforcement required to resist out-of-plane seismic forces would be No. 4 @ 48 inches on center.
a. Vertical reinforcement may be required for one or more of the following purposes:
1. to resist out-of-plane seismic forces acting on the wall,
2. prescriptive wall reinforcement,
3. additional reinforcement adjacent to an opening to compensate for reinforcement interrupted at anopening,
4. reinforcement at the ends of solid wall segments to resist the moment due to the in-plane seismicforces,
5. prescriptive reinforcement adjacent to openings, and
6. vertical shear reinforcement in solid wall segments.
Reinforcement must be the greater of that required for wind or seismic.
Vertical reinforcement required for these purposes is summarized below. All reinforcement is Grade 60.
1. The Standard does not have tables that give the size and spacing of vertical reinforcement required toresist out-of-plane seismic forces. This is due to the fact that the minimum prescriptive reinforcementprescribed in Section 4.1.3 is usually significantly more than required by analysis for this purpose, withthe exception of some stem walls designed continuous with above-grade walls without lateral supportat the slab-on-ground (see Table 4.4). If such table had been provided, the amount of vertical reinforce-ment required to resist out-of-plane seismic forces would be No. 4 @ 48 inches on center.
2. From step 2e, prescriptive vertical reinforcement required in the wall is No. 4@12 inches on center.
3. Where vertical reinforcement required to resist calculated out-of-plane seismic forces is interrupted at anopening (see 1 above), the amount interrupted needs to be located adjacent to the opening. Theamount interrupted should be as evenly distributed on both sides of the opening as practical, andshould be located within 12 inches of the edge of the opening. In this case the calculated reinforcementis No. 4 @48. Since most openings are 42 inches in width, one bar will be interrupted. Since No.4 bars@ 12 inches on center are being placed in the wall and this is 4 times the amount required by analysis(No.4 @ 48), additional reinforcement is not necessary.
4. From step 4g, vertical reinforcement required at each end of solid wall segments is 2 No. 4 barsarranged as illustrated in detail No. 3 of Figure 5.1.
5. From step 5b, prescriptive vertical reinforcement required on each side of each wall opening equal to orgreater than 2 feet in width is 2 – No. 4 bars.
6. Since horizontal shear reinforcement is required, vertical shear reinforcement is also required. Verticalreinforcement provided for out-of-plane wind resistance as required by Section 4.1.2 can be used asvertical shear reinforcement. Although it is not explicit, the prescriptive vertical reinforcement requiredby Section 4.1.3 also can be used as vertical shear reinforcement. Since the spacing of the prescriptivereinforcement required by Section 4.1.3 (i.e., No. 4@12 inches on center) complies with Section 5.2.2.3,additional vertical shear reinforcement is not required.
Seismic Design
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For SI: 1 inch = 25.4 mm; 1 foot = 0.3048 m; 1 sq. ft. = 0.0929 m2; 1 psf = 0.0479 kN/m2; 1 plf = 0.0146 kN/m; 1 mph = 0.4470 m/s
Step 7 – Design lintels for gravity loads and, if applicable, roof uplift forces. For this example, design thelintel over the 8-foot opening in the north sidewall (wall line 1) of the second story.
a. Determine the lintel design loading condition from Table 7.2. Since the lintel is in the top story, issupporting roof loads and attic floor loads, and since the top of the lintel is the top of the wall, the lintel isin a load-bearing wall; therefore, loading condition No. 2 from Table 7.2 applies.
§ 7.2§ 7.2.1T 7.2
b. Since the wall preliminarily selected in Step 1e above is a 6-inch flat wall, use Table 7.6 since it isapplicable to roofs and floors with maximum clear spans of 32 and 24 feet, respectively. Assume a linteldepth, D, of 12 inches. Note that D is the overall depth of the lintel measured from the top of theconcrete wall to the bottom of the lintel (i.e., top of the rough window opening). Under the column forloading condition No. 2 and ground snow load of 30 psf, and in the row for lintel depth, D, of 12 inches,the maximum allowable clear span of a lintel without stirrups is 5'-4". Since the clear span of the lintel is8'-0", stirrups will be required. For one No. 4 Grade 60 bar in the top and bottom of the lintel, themaximum allowable clear span is 9'-6". Tentatively use one No. 4 Grade 60 bar top and bottom in thelintel. See Figure 7.3.
HINT: In designing lintels, try to avoid stirrups if possible.
T 7.6
F 7.3
c. Section 7.2.2 requires that lintels subject to more than 600 plf of factored uplift force be designed to resistthe uplift force. Since the lintel is subjected to an uplift force of 758 plf (see step 5a above), it must bechecked to determine if the reinforcement required for gravity loads (1 – No. 4 Grade 60 bar top andbottom) is sufficient for uplift. Since the lintel is in a 6-inch flat wall, Table 7.20 is used. Enter the tableunder the column factored roof uplift force of 800 plf (since this exceeds the actual uplift of 758 plf), andin the row for a lintel depth, D, of 12 inches, observe that for 1 – No. 4 Grade 60 bar top and bottom, themaximum allowable clear span is 11'-8" if stirrups are provided. Since the allowable span for uplift isgreater than the actual span of 8'-0", 1 – No. 4 Grade 60 bar top and bottom is adequate for the gravityloads and factored uplift forces to which the lintel will be subjected.
Use one – No. 4 Grade 60 bar in the top and bottom of the lintel.
§ 7.2.2
T 7.20
d. For the lintel design selected, stirrups need to be provided in accordance with Section 7.2.1, whichrequires that No. 3 Grade 60 stirrups be provided and spaced not to exceed d/2 inches, where d is linteldepth, D, minus the cover specified. For the example lintel, assume the cover equals 11⁄2 inches, whichmeans that the stirrup spacing cannot exceed 5.25 inches ((12 – 1.5)/2 = 5.25). Stirrups must be placedthroughout the length of the lintel, except for the portion near the center of the span designated centerdistance, A, in Table 7.6, which in this case is 3'-8". The stirrup nearest each end needs to be located nomore than d/2 from the face of the support. See Figure 7.1.
Use No. 3 Grade 60 stirrups with standard stirrup hooks on each end in accordance with Figure 2.6.The stirrup nearest each end is to be located no more than 5.25 inches (i.e., d/2) from the face ofthe support. Thereafter, stirrups shall be spaced not to exceed 5.25 inches on center. Stirrups maybe omitted in the center 3'-8" portion of the span. Also, see Figure 7.3.
§ 7.2.1
F 7.1
F 7.3
Step 8 – Determine minimum width of footing that is monolithic with slab-on-ground.
From Table 3.1, “minimum width of concrete footings…,” under the column for 2,000 psf minimum load-bearing value of soil and ground snow load of 30 psf, and from the row within the portion of the table forwall Group 2, which includes 6-inch flat walls, for a two-story building with a maximum roof span of 32feet and maximum floor span of 20 feet, determine that the minimum required footing width is 22 inches.Since the dwelling does not have a basement and foundation wall, table note 5 permits a reduction of 10%in the width determined from the table. Therefore, the footing must be a minimum of 20 inches wide.
Provide minimum width footing of 20 inches.
§ 3.1.1
§ 3.1.2
T 3.1
Wind Design
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Appendix D – Design Example
For SI: 1 inch = 25.4 mm; 1 foot = 0.3048 m; 1 sq. ft. = 0.0929 m2; 1 psf = 0.0479 kN/m2; 1 plf = 0.0146 kN/m; 1 mph = 0.4470 m/s
Step 7 – Design lintels for gravity loads. For this example, design the lintel over the 8-foot opening in thenorth sidewall (wall line 1) of the second story.
a. Same as for wind design.
b. Same as for wind design.
c. Not applicable to seismic design.
Use one – No. 4 Grade 60 bar in the top and bottom of the lintel.
d. Same as for wind design.
Use No. 3 Grade 60 stirrups with standard stirrup hooks on each end in accordance with Figure 2.6.The stirrup nearest each end is to be located no more than 5.25 inches (i.e., d/2) from the face ofthe support. Thereafter, stirrups shall be spaced not to exceed 5.25 inches on center. Stirrups maybe omitted in the center 3'-8" portion of the span. Also, see Figure 7.3.
Step 8 – Determine minimum width of footing that is monolithic with slab-on-ground.
Minimum width same as for wind design in step 8.
In addition, Section 3.1.3 requires that in buildings assigned to Seismic Design Category D1, footings thatare monolithic with a slab-on-ground must be provided with one No. 4 bar in the top and bottom of thefooting as shown in Figure 4.4.
Provide minimum width footing of 20 inches with No. 4 Grade 60 bar in top and bottom.
§ 3.1.1
§ 3.1.2
§ 3.1.3
T 3.1
F 4.4
Seismic Design
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